最新刊期
期 3 ， 2018
- 摘要：Manufacturing industry of stainless steel railway vehicles has developed rapidly during the 12 th Five-Year Plan period.Traditional resistance spot welding method has some insuperable limitations,such as low appearance quality of the carbody,poor air tightness,and low productivity. While the partial penetration laser lap welding in stainless steel carbody has outstanding technical advantages compared with resistance spot welding. In this paper,a series of core technologies,key equipment and standard procedures were formulated based on the technical characteristics of laser welding in railway vehicles,including precision forming of parts,precision assembling of component,traceless welding process,intelligent quality monitoring,and nondestructive testing（NDT）. Besides,laser welding production lines and corresponding manufacture process system were established. The key technical issues of large-scale laser welding in manufacturing of stainless steel railway vehicles were analyzed,and the forecast and outlook for application prospect of laser welding technology in manufacturing industry of railway vehicles were made.关键词：laser welding;stainless steel railway vehicles;precision forming;precision assembling;traceless welding
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发布时间：2022-04-22 - 摘要：To ensure the safe and reliable operation of high-speed trains,the welded joints of bogies must have the ability to serve in wide area,such as the extremely cold regions of Northeast China and Russia. Therefore,it is increasingly important to develop the welding material for bogie with cold resistant and high toughness. In this paper,a new type of 55 G Ⅱ solid wire with high cold resistant and toughness was developed by using microalloying design. The transition behavior of droplets was observed by using high speed phase system. The mechanical properties of weld metal were tested and the fracture morphology of the specimens were observed by scanning electron microscope（SEM）. Besides,the corrosion resistance and fatigue limit of the weld metal were studied. The results showed that,the newly developed solid wire has excellent arc stability under 250 A and 150 A current conditions,such as short circuiting or breaking times and small spatter particles. The microstructure of the weld metal is mainly composed of bainite,pearlite and ferrite. The maximum impact energy at-40 ℃ is 129 J while the average one is 96 J at-60 ℃. The weight loss of 1 000 h alternate immersion corrosion is3.56% and the fatigue limit of the welded joint is 374 MPa through 1×107 cycles under the 4 stress level.关键词：bogie welding wire;fatigue performance;mechanical property;fracture morphology;corrosion weight loss ratio
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发布时间：2022-04-22 - 摘要：By using the manual MIG arc brazing,three kinds of brazing wires were tested for the butt joint of SUS304 stainless steel and Q355 GNHD weather resistant steel. The results showed that the wettability of Cu Si3 showed the highest value and the vaule was 4.02 on the SUS304 stainless steel and 3.62 on the Q355 GNHD weather resistant steel. The Cu Al8 brazed joints showed regular surface with lower defects. So the Cu Al8 wire is more suitable than the other two wires for brazing the two kinds of materials.关键词：stainless steel;weather resistant steel;MIG arc brazing;brazing wire
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发布时间：2022-04-22 - 摘要：Principle and application of the brazing were briefly introduced in this paper with summing up the brazing method used in the high-speed train manufacturing process. Then the various system components connection form of braze welding joints were analysis.The commonly used types and selection principle of brazing were introduced in the article. The brazing technology problems were discussed in high-speed train manufacturing. At last the article put forward the development direction of brazing technology in highspeed trains according to the domestic current situation of the high-speed train manufacturing enterprises and the research progress of brazing technology. The paper could provide the reference for safe and stable operation of the high-speed train and the development of the corresponding welding industry.关键词：high-speed train;brazing filler metals;brazing technology
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发布时间：2022-04-22 - 摘要：Friction stir welding（FSW）,a novel welding technology,has a extensively applied prospect in the railway vehicles production,and has been uesd in "Fu Xing"-High-Speed train. For example,we use the single shoulder FSW process for the plate of car coupler production,and use the biaxial shoulder FSW process for flat roof and bottom plate production. Based on the production technology of the plate of car coupler and flat roof,the applications of FSW in the high-speed train manufacturing were investigated in this paper.关键词：high-speed train;friction stir welding;single shoulder;biaxial shoulder
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发布时间：2022-04-22 - 摘要：Friction stir welding is a welding method without welding filler material,low heat input and small welding deformation,great joint mechanical performances. The method has played an important role in aerospace,ship,automobile,rail transportation and electronics industry. In the field of friction stir welding of aluminum alloy,the introduction and transformation of international advanced standards and the development of national standards will make the actual production process and management process more specific,more standardized and more operable,which has an important significance. In this paper,the standard applicable ranges,friction stir welding process specifications,aluminum alloy friction stir welding quality and testing requirements are analyzed between national and international standards. The national standards are interpreted. The paper has played an important guiding significance on the actual welding productions and processes.关键词：standard benchmarking;friction stir welding;national standard
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发布时间：2022-04-22 - 摘要：The application of information technology has a great impact on the industrial field. Panasonic Welding Systems（Tangshan）Co.,Ltd.,（PWST） combines digital technology and information technology in welding equipment,and develops an information welding management system "i Weld". After more than 10 years of development,i Weld has completed the transition from version 1 to 5,made extensive market applications in multiple segments,and accumulated rich experience. This paper introduces the application case of i Weld in the welding industry of high-speed train,which is a targeted scheme according to the actual demand and development direction of the user. Finally realize the ultimate goal of lean workshop operation,quality improvement and efficiency in information transformation of welding equipment,optimization of production task execution flow,guarantee of product welding quality and data mining ways,and help customers move forward on the goal of intelligent manufacturing transformation.关键词：i Weld;high-speed train;welding;intelligent manufacture;practical application
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发布时间：2022-04-22 - 摘要：This paper introduces the governance problems of welding pollutants for high speed train welding. This paper introduces the welding pollutant composition,particle size distribution and harm;This paper introduces the principle and advantages of displacement ventilation;Through the successful application of displacement ventilation in the high speed train welding workshop,the conclusions as follows:displacement ventilation can provide a good thermal comfort environment for welding workshop,and can improve the air quality in the workshop.关键词：welding;pollutant;displacement ventilation;thermal comfort;circular diffuser
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发布时间：2022-04-22 - 摘要：The residual stress of the welding joint of S355J2W+N steel was studied in this paper,and the residual stress distribution of weld seam was analyzed. The results show that the longitudinal stress and maximum principal stress of the weld area are mainly tensile stress,which decreases the trend from the center to the edge. The lateral stress of weld area is dominated by compressive stress,and the maximum value（absolute value）appears at the edge of the specimen. The residual stress is compressive stress,and the maximum value（absolute value）appears in the intermediate region of the weld and the edge of the plate. The residual stress difference between the repaired and unrepaired joints was not significant,without obvious regularity. Through the experiment,combined with the existing research conclusion,for the stress after welding butt joint structure with the annealing treatment,residual stress has little effect on mechanical properties of welded joint.关键词：bogie;repair welding;residual stress
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发布时间：2022-04-22 - 摘要：In this paper,the effect of the rectification rate on the microstructure and mechanical properties of 6082-T6 aluminum alloy FSW joints was studied systematically by tensile test,bending test,hardness test and metallographic test. The results showed that the facture occured in HAZ. The tensile strength of joint met the standard and the bend property of joint perfomed well. The softening behavior appeared in FSW joints. With the increase of rectification rate,the microstructure of different zones in FSW joints had no changes.关键词：rectification rate;aluminum alloy;microstructure;mechanical performance
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发布时间：2022-04-22 - 摘要：Aluminum profiles are widely used in the manufacture of high-speed train body,the researh was made of the residual stress,the distribution and residual stress reduction of the key parts of the bolster. Ultrasonic is adopted to eliminate stress on the simulation part,using blind hole method to measure the size of welding residual stress before and after impact,tensile,bending,fatigue test were carried out after the impact of the parts sampling. The results showed that:ultrasonic impact treatment for reducing weld and HAZ high stress zone;as the current increasing,residual stress elimination rate increases accordingly,when the current is 1.6 A,the reducing rate is 33%,the homogenization rate is 44%,welded joint tensile,bending and fatigue performances meet the requirements.关键词：high-speed train;6 series aluminum alloy;ultrasonic impact treatment;residual stress
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发布时间：2022-04-22 - 摘要：DCSP-TIG with activating flux is a new welding technology. The process was applied to joining 2219-T87 aluminum alloys.Pore-free seams with good weld appearance could be acquired in relatively low welding current. The activating flux without oxide played a key role,which could dissolve the oxide film on aluminum surface,and reduce or eliminate the pores in joint by combining with hydrogen in arc. Compared with the variable polarity plasma arc welding,DCSP-TIG with activating flux had better mechanical properties due to the pore-free and fine-grain microstructure in the fusion zone.关键词：2219-T87;DCSP-TIG welding;activating flux;variable polarity plasma arc welding
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发布时间：2022-04-22 - 摘要：P355 NL1 low alloy steel is a commonly used material for bogie frame. In this paper,the tensile,impact,flexural and fatigue tests of the welded parts of P355 NL1 low alloy steel and its repairing part are carried out. The result shows that it’s not bad for microstructure of welding repair and the grain size of the retained lower welding layer can be refined. There is no obvious decrease in the welding hardness after single pass welding. The tensile failures of the two parts happened on the base metal,the welding repairs have no effect on the static load strength. Comparing with original welding part,due to the welding of the last remaining welding joints parts played a role in heat treatment,grain refined,improved tissue distribution,the impact toughness and fatigue strength of repairing part is improved.关键词：bogie frame;P355NL1;welding repair;mechanical properties
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发布时间：2022-04-22 - 摘要：The effect of pre-welding cleaning on the S-line and properties of the FSW joints of the aluminum alloy thick plates was studied by contrast of the specimens with pre-welding cleaning and without pre-welding cleaning. The following conclusions were drawn from a series of experiments. The pre-welding cleaning helped to improve joint microstructure. At the same time,the effect of pre-weld cleaning on the FSW joint was shown to weaken the S-line,especially the width of the S-line. The pre-weld cleaning could also improve the mechanical properties of joints.关键词：friction stir welding;pre-welding cleaning;microstructure;S-line;mechanical properties
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发布时间：2022-04-22 - 摘要：In this paper,specimens of stress corrosion susceptibility under different welding processes were prepared by friction stir welding and MIG welding,on 6005 A-T6 aluminum alloy profiles respectively and exposed to the same test environment and inert environment,The method of comparison was used to assess the susceptibility to stress corrosion cracking. The farther the ratio deviates,the higher the susceptibility to cracking. It was shown that there was a slight difference between the stress corrosion susceptibility of friction stir welding and that of MIG welding,the values were 0.956 and 0.963,respectively,and neither of them showed stress corrosion tendency in 3.5% Na Cl solution. It would be seen that there was no brittle fracture characters on the SEM images of the two kinds of joints in the inert environment and the corrosive environment. The fracture morphology was dominated by dimples formed by plastic fracture.关键词：6005A-T6 aluminum alloy;friction stir welding;MIG welding;stress corrosion susceptibility;micro fracture analysis
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发布时间：2022-04-22 - 摘要：It is very important for the safe operation of the train to make sound connections between the dissimilar metal joints in the high-speed train manufacturing process. In order to overcome the shortcomings of the current welding of copper and aluminum,this paper introduces a method to connect aluminum plate and copper plate by resistance soldering. Under the parameters of orthogonal test design,it is successful to braze a sample of large area after a series of experiments. At the same time,when observing the microstructure of Al-Cu resistance soldered joint using SEM,it is found that in the appropriate soldering specifications the solder material distributes and joints to the parent metal,atoms of major elements in the solder and the parent metal Al and Cu can mutual diffusion,infiltration and achieve a combination between atoms,the solder microstructure reveals no obvious defects.关键词：resistance soldering;soldered joint;diffusion;microstructure
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发布时间：2022-04-22 - 摘要：Low cycle loading testing method with the PWS-100 low frequency fatigue machine and high cycle loading testing method with the QBG-100 high frequency fatigue machine were used to test the A6605-T6 aluminum alloy welded joints. The dynamic strain test machine was used to test the strain value of the above two fatigue method. The results showed that the strain value of No.14 all changed after the first time loading under the low cycle loading method but the strain value didn’t change after second time loading to10 million times loading. With the cycle times have changed from 10 thousand times to 10 million times,the strain value of N0.14 didn’t change. So the results showed that the welded joints didn’t show new plastic deformation with the increase of the cycle times,so the welding residual stress didn’t continue to relax with the incrrease of the cycle times.关键词：residual stress;A6005-T6 aluminum alloy;low cycle loading;high cycle loading;strain value
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发布时间：2022-04-22 - 摘要：Manufacturing technology plays an important role in the R&D and manufacturing of high-speed train,as the technological support to improving the manufacture quality,efficiency and capacity of production. This paper mainly introduces the key manufa-cturing technology of China Standard EMU Trains’（CR400 BF） bogie frame,which is designed and produced by CRRC Changchun Railway Vehicles Co.,Ltd. Final1 y,the research direction for improving manufacturing technology is proposed.关键词：China standard EMU;CR400BF;bogie frame;manufacturing technology
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发布时间：2022-04-22 - 摘要：In this paper,6005 A-T5 aluminum alloy plate was friction stir welded using a high welding speed. The microstructure evolution of different zones of the joint were investigated using various characterization methods. Mechanical properties of the joint were evaluated through tensile tests and micro-hardness measurements. It was shown that the nugget zone had fine equiaxed grains due to the dynamic recrystallization. The thermo-mechanically affected zone was characterized by plastic deformed and recovered structure because of the stains and thermal cycle subjected during the FSW process. The heat affected zone retained the same grain structure as the parent material,but grain coarsening occurred,which was also attributed to the thermal cycle during welding. The tensile strength of the joint reached 82.5% of the base material,and all the tensile specimens were fractured at heat affected zone,which was confirmed as softening region by microhardness measurement. In the condition of 106 cycles,fatigue limit at 132.9 MPa.The presented data of fatigue test provides solid base for pratical application.关键词：high speed friction stir welding;6005A-T6 aluminum alloy;joint microstructures;mechanical property
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发布时间：2022-04-22 - 摘要：The high speed train technology in China has development rapid in recent years,put forward more stringent requirments for break materials. The copper-base powder metallurgy friction material has an irreplaceable advantage in braking. In this paper,the research progress of copper-base powder metallurgy friction material was briefly introduced through the composition ratio and process conditions,then suggested that optimizing the composition and stabilizing process was an effective way to improve the quality of products.关键词：high speed train;copper-base powder metallurgy friction material;composition ratio;process conditions
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发布时间：2022-04-22 - 摘要：The coupler panel is an important part of the rail vehicle. In order to study its deformation and residual stress after welding,based on thermal elastoplastic method,taking 6005 A-T6 aluminum alloy coupler panel as the research object,the multi-layer welding deformation and residual stress field were numerically simulated,and the process optimization plan was put forward. The results show that there is a large longitudinal residual tensile stress in the vicinity of the weld seam after the welding of the coupler,and the transverse residual stress in the arcing place and the arc extinguish place is higher. The maximum equivalent stress of Von-Mises occurs at the joint of the front weld and the back weld. By setting proper reverse deformation,the welding deformation can be effectively reduced without affecting the residual stress,while ensuring the flatness and bearing capacity of the coupler panel. The research results have certain guiding significance for the actual welding production of the coupler panel.关键词：aluminium alloy;multi-pass weld;finite element analysis;welding deformation;residual stress
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发布时间：2022-04-22 - 摘要：In the manufacturing industry of rail transit,due to a large number of and wide distribution of welding equipment,it is difficult to supervise and trace the production management and welding quality. In order to strengthen the management of welding process in the aluminum alloy plant,a network was build between the server and welding equipment to achieve the factory LAN and welding equipment information interoperability based on the manual welding machine as the smallest unit in this paper. Through the construction of intelligent management system of network welding data,combination of factors such as cost optimization and examination basis,the efficiency and the quality of products,can be improved. Meanwhile,the timeliness,the reliability and the accuracy of information and communication also can be ensured.关键词：welding equipment;network;intelligent management;interoperability
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发布时间：2022-04-22 - 摘要：Temperature is the key factor in the accuracy of residual stress test by ultrasonic. The effects of temperature on the base metal,the heat affected zone and the weld of A7 N01 P-T4 aluminum alloy welded joints were studied in environment lab,and then the temperature modified model was established in this paper. The results showed that when the temperature was at lower temperature（038 ℃）,the temperature played the leading role in the effect on acoustoelastic effect,but the relationship between acoustoelastic effect and temperature had nothing to do with the testing materials. When the temperature raised,the elastic modulus E and density ρ changed obviously. When the modified temperature was at 238 ℃,the temperature modified model was Δσ =K [t-（0.414 05 T-0.874 06）].关键词：temperature;ultrasonic residual stress testing;acoustoelastic effect;modulus of elasticity
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发布时间：2022-04-22 - 摘要：Studies the S355 J2 W+N microstructure in S355 J2 W+N welded joint by repair welding,analyzes the characteristics of weld zone and heat affected zone through different times of repair welding. The results show that the microstructure of upper layer and the bottom are not influenced apparently by repair welding. As the increase of the times of repair welding pearlite in the weld metal tapers,ferrite grain grows up. When welded by the same times,from top to bottom along the thickness of the joint direction,HAZ acicular ferrite in the coarse grain zone has a tendency to reduce,HAZ incomplete uneven grain size are normalized area,the organization has kept rolling state characteristics of the parent metal.关键词：bogie;repair welding;microstructure
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发布时间：2022-04-22 - 摘要：The influence of different pulse frequency on the weld formation and microstructure of A6 N01 aluminum alloy welded joint is studied. The results show that the different pulse frequencies have no obvious influence on the formation and defects of the weld.The microstructure of weld joints with different pulse frequency is typical dendritic structure. The fusion zone is columnar structure near the weld side,and the other side is equiaxed crystal near the base. The grain size of heat affected zone is larger than that of parent metal. The parent material is a typical recrystallized tissue. It can be considered to choose different pulse frequencies for welding.关键词：A6N01 aluminum alloy;pulse frequency;weld formation;microstructure
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发布时间：2022-04-22 - 摘要：The local plastic deformation and redistribution of residual stress would occur under the superposition of static load stress and welding residual stress. The peak residual stress will decrease after the static stress unloaded. This paper was based on this theory and took A6005 A-T6 aluminum alloys welded joints as the objectives to study the static loading conditions and gradual loading conditions under the evolution of residual stress. The results showed that the residual stress had relaxed in high degree after static load stress（the loading stress was 150 MPa）,the peak value had changed from 125 MPa to 48 MPa of the longitudinal residual stress and the peak value had changed from 155 MPa to 56 MPa of the transverse residual stress. The reason was that the residual stress had relaxed due to the superimposion of external load and residual stress beyond the yield strength of the material had been plastic deformation. The welded structures could be statically stretched in some degree before using and could remove some residual stress especially the peak residual stress.关键词：static load stress;welding residual stress;loading step by step;plastic deformation;stress relaxation
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发布时间：2022-04-22 - 摘要：Correlation of stress intensity factor and defect size for welded joints of high-speed train bogie frame was analyzed and calculated by means of fracture mechanics principle for surface linear defect and root continuity defect. More specific results were thus provided on allowable defect size under different stress range based on material properties of welded joint. Results show that stress intensity factor of crack tip increased with flaw depth and stress range, but decreased with the ration of depth and semi-length.Furthermore,flaw tolerance depth was significantly reduced with the increase of stress level.关键词：weld;bogie frame;fracture mechanics;defect;damage tolerance
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发布时间：2022-04-22 - 摘要：This paper aims at the problem of the repeated repair in welding of bogie beam tube and longitudinal beam when face in the weld depth isn’t enough. It is different from the way in the past in which increase the current to add the welding depth. This paper proposes that use the advantage of automatic welding robot. To weld the plate of T joint through using the methods of the welding of pull the arc which it is hard to manual welding,using the special command to adjust arc shape,using the different welding position when welding the different layer. It is achieve the target that only increase welding depth but no additional current,and reduced the welding stress and welding deformation, which it can be useful for the similar welds of automatic welding robot.关键词：bogie;T joint welding;automatic welding robot
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发布时间：2022-04-22 - 摘要：Key dimensions of car body composition of Intercity EMU have speed of 200 kilometers per hour involve length,height,deflection and entrance height.After welding length reduced,height of the car body and entrance height decrease,the two ends bend upwards. Process allowance can control length Effectively. Widen the side wall before welding can control height Effectively.Prefabricated deflection on side wall and Fixture can control deflection of the car boday Effectively.关键词：car body composition;height;deflection;process allowance
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发布时间：2022-04-22 - 摘要：The surface radian,surface roughness and surface adhesive materials will affect the detection errors of residual stress of the components when the vehicles were under ultrasonic wave residual stress detection,then the detection results will affect the residual stress distribution and peak value greatly. This paper is focused on the research of the effect of surface radian,surface roughness and surface adhesive materials of A7 N01 aluminum alloys. The results showed that the arc probes should be adopted when the surface was in the circular arc transition. The abrasive papers should be used to polish the sandblasted surface and it would promote the detection precision but the detection results would be affected if the surface was in excessive polished and formed additive stress layer and destroyed the surface. The painting coating could be detection directly and the painting layer did not affect the first critical incident angle greatly but affect the t0 greatly. So the t0 must be amended.关键词：surface coupled;A7N01 aluminum alloys;residual stress;surface radian;surface roughness;surface adhesive materials
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发布时间：2022-04-22 - 摘要：In view of the problem of weld grinding in the welding process of high speed EMU bogie frame,intelligent welding technology for different types of welds is studied with advanced intelligent manufacturing technology. The system can compare the physical appearance with the control system model in real time through the visual inspection system,and plan the grinding path and the cutting feed parameters,Through the design of intelligent grinding system to achieve high-speed EMU bogie frame of various types of weld grinding,in order to achieve the goal of improving production efficiency,enhancing product quality and reducing labor intensity.关键词：high speed EMU;bogie frame;intelligent grinding
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发布时间：2022-04-22 - 摘要：Experiments and analysis were made on A7 N01 S-T5 aluminum alloy welded joints. Nominal S-N curves and the fatigue strength under different survival rate were obtained through the tension-tension fatigue tests. The hot spot stress,gap stress were obtained by finite element method,and then the fatigue properties were evaluated by using the nominal stress method,hot spot stress and gap stress method. The results showed that the mean fatigue strength Δσ was 45.77 MPa by the tension-tension load fatigue test,and after corrections of two standard plus or minus deviations,the fatigue strength ΔσKwas 39.89 MPa under the 95% reliability. The hot spot stress concentration factor was 1.034 and the hot spot stress fatigue strength was 47.39 MPa. The gap stress fatigue strength was123.03 MPa. The fatigue strength under the gap stress method had the largest value,the value under the hot spot stress method was in the medium and the value under the nominal stress method was the smallest. The nominal stress method was more conservative than the other two but the hot spot stress method and gap stress method both need to evaluate the detailed factors and analyze the stress condition accurately so as to make sure the safety of high-speed trains.关键词：A7N01 aluminum alloy welded joints;fatigue strength evaluation;nominal stress method;hot spot method;gap stress method
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发布时间：2022-04-22 - 摘要：Through the tensile testing,bend testing,hardness testing and analysis of the microstructure,this paper studied the conventional mechanical properties and the microstructure of 3 mm ferritic stainless steel welded joints by MAG,CMT,PAW and TIG. The results show that:The conventional mechanical properties of the joints by all these four welding processes are accepted. The austenitic stainless steel welding wires were applied to the MAG,CMT and TIG joints. The microstructure of weld is the lath ferrite or reticulum ferrite in the austenitic matrix,and these joints have higher hardness. The microstructure of autogenous PAW weld is bulk ferrite with homogeneity of the parent material,and its hardness is less than that of the parent material. The coarsening of ferrite grain has an adverse effect on the strength and hardness of the joint.
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发布时间：2022-04-22 - 摘要：Laser-MAG hybrid welding technology was used to weld the non-groove T-joint S355 J2 W bogie frame with 12 mm thickness in order to obtain the welding by one side with back formation joints. The focus location offset along the two directions due to Tool Center Point（TCP） change in automatic welding was described,which are defocus offset and the offset along vertical plate surface of T-joint. According to the test results of the appearance and metallographic examinations,the influence of offset along the above two directions on welding quality is discussed. The maximum allowable offset ranges were obtained,which are-2.5-1.5 mm of defocus and12 mm along vertical plate surface. In this range,a stable welding by one side with back formation can be achieved.关键词：bogie frame;T-joint;laser-MAG hybrid welding
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发布时间：2022-04-22 - 摘要：A testing device has been designed for measuring the straightness of welded joints in rails. Machine movement control is realized by using PLC contr-oller,the multi-function data acquisition card was used to collect data,and the Labview software program was utilized to realize processing,displaying and storage of measurement data. Through a large number of measurement experiments,we confirm that the mechanical design of the testing machine can meet the requirements of long-term measurement reliability because of its high repeatability;At the same time,the result of contrasting the Germany SEC electronic measurement data curve and the straightness degree shows that system measuring accuracy of the testing machine is very high,and it can satisfy the requirements of measuring standards for straightness of welded joints in rails. This research will provide the reference for developing promotion stationary straightness measuring machine in the future.关键词：rails;welded joints;straightness measuring;stationary testing machine;measurement accuracy
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发布时间：2022-04-22 - 摘要：In this paper,the welding parameters in friction stir welding of 6005 A-T6 Al alloy extrusions used in side wall of metro train were optimized. Based on the welding parameter window with rotational speed of 1000-2100 r/min for and welding speed of500 2 200 mm/min obtained in preliminary experiments,a spindle speed of 1 500 r/min and welding speed of 1 100 mm/min were determined as the optimal parameters via comparing the appearing quality of welding seam. Metallographic analysis and tensile and bending tests were performed for joints welded with different axial forces. With a spindle speed of 1 500 r/min,welding speed of 1 100 mm/min and axial force of 13.5 k N,defect free joints could be obtained,while the tensile strength reached 80% of base metal and no fracture occurred in 180° bending tests.关键词：friction stir welding;6005A-T6 Al alloy extrusions;mechanical properties;process parameter optimization
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发布时间：2022-04-22 - 摘要：Different rotation speeds were used on bobbin friction stir welding 6005 A-T6 aluminum alloy of 4 mm thickness. Through the research of tensile test,bending test,metallographic experiment and microhardness test,the results show that with the travel s peed of 500 mm/min,the surface of the welded joint is regular and no cavity is found in the weld at the rotation speeds between500 r/min and 600 r/min. The microhardness of the stir zone has a little change,the width of the heat affected zone increases,the lowest microhardness is found in the advancing side with the rising rotation speeds. Tensile strength of the welded joint first increases and then decreases with the rising stirring speeds,when the rotation speeds is 500 r/min,the tensile strength reaches the peak of 220 MPa,which is 86.47% of the tensile strength of the parent material.关键词：6005A-T6 aluminum alloy;bobbin friction stir welding;mechanical property
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发布时间：2022-04-22 - 摘要：Structure of aluminum alloy driver’s cab on high speed EMU was introduced. The welding technique and welding difficulty of the driver’s cab and components was elaborated in detail. Aiming at eliminating porosity and irregular surface of welds in medium thick board,and distortion in the front wall. Its complex 3 D space structure caused locality wave distortion on the three-dimensional curved roof and outer contour size of the aluminum alloy driver’s cab was unqualified,bad welding quality of over-head position welding in driver’s cab,further studied the welding process of the cab,analyzed the causes of welding problems,and formulated reasonable process measures,effectively ensuring the welding quality of the cab to meet the design and operation requirements.关键词：high speed EMU;aluminum alloy driver’s cab;welding difficulty;process measures
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发布时间：2022-04-22 - 摘要：Powder particle size is the key factor that affects wear resistance coating. The effect of WC granularity on the microstructure and properties of WC-Ni brazing coatings was studied. Three WC-Ni wear-resistant coatings with different WC sizes were prepared by flame brazing technology. The microstructure and properties of the coating were analyzed by scanning electron microscope,energy spectrometer,microhardness tester and rockwell hardness tester. The results show that:With the increase of WC particle size,the metallurgical reaction degree of Ni solder and WC enhanced phase decreased. When WC particle size is 18 23 μm,long strip Ni W phase appears in the overlayer of coating interface. When the WC particle size is 250380 μm,the rockwell hardness of the coating is the highest,and the coating has the best wear resistance.关键词：brazing;WC;wear resistant coating;microstructure;mechanical properties
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发布时间：2022-04-22 - 摘要：The research status of carbon steel welding used in railway train has been summarized in this paper. The carbon steel,welding materials and welding technology are analyzed deeply. The development process of the carbon steel and welding materials has been discussed. The development and application of high-strength steel will promote the development of carbon steel used in railway train. And this will bring the update of welding materials with higher-properties as well. The main welding technology applied in steel railway train has been introduced. The resistance spot welding and laser welding are the welding methods with low heat input,and the wide application prospect of them in railway train has been illustrated. The future directions of carbon steel welding applied in highspeed train are pointed out:the development of new materials,update of new technology and application of computational emulation technology will give a great push to the carbon steel railway train.关键词：railway train;carbon steel;welding materials;welding technology
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发布时间：2022-04-22 - 摘要：In the track of metro vehicle manufacturing process,stainless steel body side wall beam adopting column structure has the characteristics of large size,welding parts,how to predict and control the welding deformation,to ensure that the design size is an urgent research topic in rail vehicle manufacturing plant. Firstly,the long-term tracking of a side wall unit after welding flatness were found,the welding deformation of the side wall of the unit;secondly,the establishment of a local finite element model,the simulation of welding deformation using the finite element software,analyze the reason of side wall unit deformation trend,and puts forward the applied reverse before welding two kinds of beam deformation and increase the process control measures;finally the feasibility of this method is proved,the control unit of the factory wall stainless steel side welding deformation has important significance.关键词：welding deformation prediction;welding deformation control;welding simulation;finite element
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发布时间：2022-04-22 - 摘要：The technical difficulties of welding by one side of J groove welding in frame beams are analyzed. According to the results obtained by a lot of the experiments,the MAG breakdown welding method is adopted. The welding is proceeded from left to right,and the positioner is employed in order to achieve a one-time welding at the PC position. The result is that a satisfactory process of welding by one side is obtained,which is important to ensure the weld quality and improve the produce efficiency.关键词：J groove;welding by one side;breakdown welding method
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发布时间：2022-04-22 - 摘要：ASTM A588 is a high strength low alloy steel in the American Standard ASTM A588 A/588 M-15 for anti-atmospheric corrosion. Based on the structural design of the car body,research on technology test for the ASTM A588 high strength low alloy steel butt joints with different groove form,tensile and bending tests are conducted for 8 HV and 4 DHV groove welded joints at room temperature,and the low temperature impact test is conducted for the weld and heat affected zone at the temperature of-40℃. The results show that,the 8 HV welded joint has high tensile strength,good plasticity and ductility,and has good low-temperature impact toughness,have reached the standard requirements of AWS D1.1-D1.1 M-2015,recommend butt joints with a plate thickness of 8 mm and below have a single-sided groove form,provide a theoretical basis for the design of welding structure of vehicle body.关键词：ASTM A588;groove type;mechanical properties
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发布时间：2022-04-22 - 摘要：Combining with the assembly of steel structure of railway vehicle car body,the research simulated technical process utilizing DELMIA. Based on the technical process,the research created process environment,simulated assembly welding process and analyzed product assembly and equipment accessibility. Combining with ergonomic analysis and optimizing adjustment of technique,equipment and the layout of product line,the research is helpful to improve assembly quality and efficiency.关键词：railway vehicle;car body;assembly welding process;simulation;analysis
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发布时间：2022-04-22 - 摘要：Microstructure and mechanical properties of the ZGMn13 welding joints were tested which were made by the laser-arc hybrid welding and SMAW. The results shows that:Laser-arc hybrid welding can improve the productivity greatly. Both the weld joints got excellent properties. Precipitation of saturated carbides were found in the heated affected zone of both methods. The weld joint of laserarc hybrid welding shows more excellent toughness properties as the less precipitation content and smaller grain size.关键词：ZGMn13;SMAW;laser-arc hybrid welding;microstructure
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发布时间：2022-04-22 - 摘要：Laser power and focus distance are important parameters that can influence the laser welding quality,for researching the influence of these parameters on stainless steel laser welding line properties,in this paper a laser welding system is established to do welding test with different laser power and focus distance. the changing of welding line and tensile strength are contrasted. The results indicated the width and penetration of welding line will change using different laser power. The penetration would be much more sensitive and the width would change little. With the change of focus distance,the width and penetration had the same variation trend.And we would get much bigger penetration when using a much lower laser focus position. To part-penetration laser welding line,the tensile strength and width had positive correlation and had less relationship with the penetration.关键词：laser welding;laser parameters;welding mechanical properties
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发布时间：2022-04-22 - 摘要：The effects of different pulse frequency on the tensile strength,bending properties and micro-hardness of the A6 N01 aluminum alloy welded joints were investigated in this paper. The results showed that the welded joints at fx=1 Hz had the highest mean value of the tensile strength and the highest strength coefficient,and the welded joints at fx=0 Hz had the highest mean value of the elongation and strength-ductility balance and the best comprehensive strength and toughness. But the effect of different pulse frequency on the microhardness of the welded joints was not obvious. Hence the weld joints had the best combination properties when the pulse frequency was 0 Hz.关键词：A6N01 aluminum alloy;pulse frequency;tensile strength;microhardness
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发布时间：2022-04-22 - 摘要：Microstructures and properties of 4 mm AZ31 B magnesium alloy welded joints welding by TIG were studied respe-ctively through tensile tests,bending tests,hardness tests and analysis in this paper. The tensile test results showed that,all the specimens were broken in the heat affected zone and the tensile strength satisfied the standard. The grain size of the TIG weld zone is relatively small,the organization is α-Mg solid solution,the grain boundary is dispersed with the black β-Mg17 Al12 precipitation phase,and the grain size of the heat affected zone is longer than that of the base metal. The hardness of the base metal is higher than that of the heat area and weld,there is a softening phenomenon in the joint heat affected zone. It also can be seen that the cracked position of the pulsating tensile fatigue fracture specimen of the 4 mm AZ31 B magnesium alloy TIG welding joint（removed excess weld metal） is in the heat affected zone.关键词：AZ31B magnesium alloy;TIG welding;microstructure and mechanical performance;fatigue
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发布时间：2022-04-22 - 摘要：Aiming to investigate the effect of welding thermal cycle on microstructure properties of aluminum alloy welded joints in the production process of aluminum alloy carbody,A5083 P-O and A7 N01 P-T4 aluminum alloys were welded separately by using same welding parameters and various welding thermal cycles in same welding environment and constrain condition. The welded joints were analyzed by means of non-destructive examination,metallography and hardness measurement. The test results showed that the A5083 PO and A7 N01 P-T4 had different hot crack tendency,which provided a theoretical basis for multiple repair in the production.关键词：welding thermal cycle;hot cracking;metallographical structure;hardness
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发布时间：2022-04-22 - 摘要：Possessing high strength and toughness,ultra high strength aluminum alloy is a kind of structural material,which has good application value and can be applied widely in the aerospace,military and rail transit fields. The research progress and development situation of strengthening-toughening of ultra high strength 7000 aluminum alloy（Al-Zn-Mg-Cu） both in domestic and foreign countries have been fully summarized. The various new technologies for improving ultra high strength aluminum alloys properties have been commented,the research progress and development of its welding technology are also summarized. For the research status and existing problems of ultra high strength aluminum alloys,the main directions of future research should include the optimization of the content of main alloying elements,the addition of new micro-alloying elements,the adoption and development of new preparation technologies,and the existing welding technologies,to promote the application of high strength aluminum alloys in different fields.关键词：Al-Zn-Mg-Cu;composition optimization;heat-treatment;molding technology;welding
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发布时间：2022-04-22 -
Shrinkage strain based numerical simulation of FSW process of aluminum alloy floor of metro vehicles
摘要：The friction stir welding process of 6005 A-T6 aluminum alloy metro floor was simulated by employing shrinkage strain method based on sequential thermodynamic coupling approach. In order to obtain the shrinkage strain,a thermal elastic-plastic finite element analysis of the local structure of the floor was carried out firstly by using equivalent heat source model and sequential thermodynamic coupling method. The welding induced distortion of the floor was calculated according to the obtained shrinkage strain,and the calculated results were compared with the experimental measurement results. The comparison results show that the welding deformation trend calculated by finite element method is highly consistent with the actual measurement results,and the error between calculated and experimental measurement results is within 0.5 mm. It is verified that the employed methods in this paper are feasible for predicting FSW welding induced deformation of large components. Then,the reasonable mitigating process of welding induced deformation should be adopted for the large FSW welded structures,such as the aluminum alloy floor of metro vehicles mentioned in the paper.- 44
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发布时间：2022-04-22 - 摘要：This paper studies the influence of oxide film on the performance of 6005 A-T6 aluminum alloy BT-FSW joints through the analysis of tensile test,bending test and microstructure. Without removing off oxidation film,the joint produces the C-shaped S line.The tensile strength of the joint is 184.3 MPa,72.2% of the strength of the parent material. The bending of the joint is not qualified.With removing off oxidation film, the joint does not show an obvious S line. The joint is divided into WNZ,TMAZ,HAZ and BM. The tensile strength of the joint is 219.3 MPa,86% of the strength of the parent material. The bending of the joint is qualified.关键词：BT-FSW;6005A-T6 aluminum alloy;oxidation;mechanical property;microstructure
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发布时间：2022-04-22 - 摘要：Based on the theory of acoustic elasticity,the residual stress of butt joint of 12 mm thick Q345 C steel was measured by critical refraction longitudinal wave method. During the test,a 2.5 MHz frequency probe was used to get the residual stress distribution in different regions of butt joint. The ultrasonic propagation velocity will be affected in the process of spreading by the size,morphology and microstructure of the material,based on different regions of welded joints were calibrated by the stress coefficient K value of each area,improve the residual stress of the joint test precision welding of Q345 C steel. By modifying the influence of the microstructure difference on the ultrasonic velocity,the engineering application of the critical refraction longitudinal wave method to test the residual stress is promoted.关键词：longitudinal critical refraction wave;residual stress;Q345C steel;acoustic elasticity
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- 150
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发布时间：2022-04-22 - 摘要：Specimens of the 7 N01 aluminum alloy with different grain sizes were prepared by means of heat treatment in this paper in order to analysis the grain size qualitatively. The stress constant K of the specimens after heat treatment was calibrated by uniaxial tensile calibration test. The results showed that the stress constant K increased with the material grain size increasing. The author built the ultrasonic testing platform in this paper. The nominal t0 of the specimens was get based on the cross correlation calculation between reference waveform and capture waveform. The material t0 was also positively associated with the grain size. The relationships between K,t0 and voltage attenuation were established in this paper. Then, the constitutive equation of K,t0 and voltage attenuation was fitted. Therefore,the modified model between the attenuation of LCR wave and the propagation time was established in this paper,and the change of K and t0 were represented by the voltage amplitude.关键词：residual stress;LCR wave;attenuation;grain size
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发布时间：2022-04-22 - 摘要：The residual stress distribution of SUS301 L-MT welded joints by the processes of MIG welding,laser welding and laserMIG hybrid welding were studied X-ray diffraction of two dimensional detector. The results showed that residual stresses under the three welding processes were distributed in "M" pattern,with tensile stress in weld zone and HAZ zone and compressive stress in base zone. The peak stress value was in HAZ zone. The peak longitudinal stress of 631 MPa and peak transverse stress of 400 MPa were found in the MIG welded joints. The residual stresses of laser welded joints and laser-MIG hybrid welded joints were almost the same,with the peak longitudinal stress 490 MPa and peak transverse stress 360 MPa.关键词：two dimensional detector;X-ray;SUS 301L-MT stainless steel;welding residual stress
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发布时间：2022-04-22 - 摘要：A new kind of railway vehicles aluminum alloy corbel structure was designed companied with the advantages and characreristics of FSW technology used for aluminum alloy welding,The detailed MIG welding combined with FSW welding technique shceme was designed according the structure feature and manufacture precision accuracy and then the manufacture structure was designed to prevent the deformation.The results showed that the MIG welding technology could be used under the pre-assembly and the FSW welding technology could be used under the outer straight welded joints. The combined technology both improve the environment and quality.关键词：FSW;MIG welding;corbel;railway vehicles
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发布时间：2022-04-22 - 摘要：Low density high manganese Fe-25 Mn-8/10 Al-1 C steel,a new lightweight high alloyed high carbon wear resistant steel,has extraordinary ductility and high tensile strength. This steel also has a larger tendency of cracking and hardening because of high carbon equivalent and aluminum content. The results showed that:the small deformation and good the performance of the joint was obtained due to the suitable welding heat input;minimum hardness value of the weld region,hardness value increased with the increase of the distance from the weld centerline;the hardness value of weld region and HAZ zone increased with the increase of the aluminum content,meanwhile,some strip ferrite is distributed in the austenite matrix of 10 Al steel.关键词：low density steel;TIG welding;welded joint;microstructure;mechanical properties
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发布时间：2022-04-22 - 摘要：The numerical model was established to simulate the 30 mm-thick bobbin tool friction stir welding process,which calculated the temperature field and flow field of two different bobbin tools. It is implied that the high temperature area is near the shoulder,which reduced along the depth to the central plane of the thick plates. The temperature in retreating side is higher than the advancing side. Using the cone-shape probe caused higher temperature than cylinder-shaped tool. It is indicated that material near the FSW shoulder flows more fiercely than inside zone. It flows more turbulently using the screw thread structure than the parallel-grooves probe,which is coincide with the weld shape results.关键词：bobbin tool friction stir welding;probe shape;temperature field;flow field;weld shape
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发布时间：2022-04-22 - 摘要：The residual stress of the S355 J2 W steel MAG welded joint was measured and analyzed by X-ray diffraction method and ultrasonic critical refraction longitudinal wave method. The results show that:the X-ray diffraction method and ultrasonic critical refraction longitudinal wave method can be used for S355 J2 W steel MAG welded joint residual stress measurement. The residual stress value of the ultrasonic method is 30 40 MPa larger than that of the X-ray method in the weld and heat affected zone. The distribution of residual stress in each test area is similar,and the residual tensile stress is larger in the weld and heat affected zone,and the base metal which is away from the center of the weld is residual compressive stress. The residual stress peak of the central area of is greater than the starting arc region and the ending arc region.关键词：S355J2W steel;MAG welded joints;residual stress
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发布时间：2022-04-22 - 摘要：The welding technology of car body and bogies is the key technology in the manufacture of high speed train production.Based on the bogies producation project plan of the intelligent welding production lines that including operations management system,welding process management system,production line control system schemes,connect the multidimensional factors of production,which provided the EMU（electric multiple unit） bogies intelligent welding production lines solution.关键词：intelligent manufacture;bogie;digital production line
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发布时间：2022-04-22 - 摘要：The X ray diffraction method（XRD） was used to test the welding residual stress in the same part of the side beam of the bogie in the processes of production and fatigue test. The change rules of the welding residual stress in the processes of production and service were obtained,which provided theoretical support for improving the manufacturing process of the bogie. The results showed that the surface for incoming side beam existed compressive stress. Residue pressure with non-uniform distribution and high tensile stress was found in the bogie parts after welding and heat repairing. After heat treatment, welding residual stress was greatly reduced,the residual stress tends to be uniform. After sandblasting,the residual stress on the beam surface was changed from tensile stress into favorable compressive stress,which benefited the fatigue property. After frame fatigue test of 6 million cycles,the residual compressive stress relaxation did not occur. After fatigue test of 12 million cycles, the residual compressive stress on the surface significantly decreased,while the stress was relaxed and redistributed to be more uniform.关键词：X ray diffraction;welding residual stress;heat treatment;sand blasting treatment;fatigue test
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发布时间：2022-04-22 - 摘要：Magnetic pole box structure is an important structure in the production of permanent magnet motor. Its welding reliab-ility has a direct influence on the stable operation of the motor. Laser welding were used to weld the shell（316 L stainless steel） and substrate（Q345 D） of magnetic pole box. The sealing,mechanical vibration and thermal shock of welded magnetic pole box were tested. Magnetic pole box were sealed and the weld seam were examined by penetration,metallography and hardness. The results show that the sealing property of the magnetic pole box with laser welding were qualified,there were no crack in the inspection of the weld,the metallography test and the microstructure hardness test were all qualified.关键词：laser welding;permanent magnet motor;magnetic pole box
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发布时间：2022-04-22 - 摘要：The welding distortion of aluminum alloy end walls was taken as the example. The reasons of welding distortion of Al alloy end walls with plate-girder structure were analyzed and a suit of process program for producing end walls was summarized with preferable assembly sequence,high assembly quality,suitable welding procedure and prefabricated distortion to reduce welding distortion. By these means,the difficulty of repair and workload were reduced,the efficiency of production was increased,and high standard quality products were made.关键词：end walls;welding distortion;assembly sequence;prefabricated distortion
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发布时间：2022-04-22 - 摘要：This paper mainly researches on the contact-reaction brazing of AZ31 magnesium alloy and 6061 aluminium alloy by adding the Zn-7 Al metal middle layer,and analyzes the microstructure and mechanical properties of brazing joint by 3 D digital video microscope and hydraulic universal testing machine. The result shows the joint strength of the middle layer contact-reaction brazing of AZ31/Zn-7 Al/6061 is higher,than that of the direct contact-reaction brazing with Mg/Al. In the middle layer,Zn is a suitable matrix metal because Zn can react with Mg and Al to generate good properties phase which has a certain strengthened effect on the properties of the joint.关键词：magnesium alloy;aluminium alloy;contact-reaction brazing;metal middle layer
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发布时间：2022-04-22 - 摘要：High speed train and high speed railway in china are booming at a very rapid pace. Relevant state departments proposed that we should "continue to develop the energy conservation and environmental protection technology system in depth for both high speed railway and high speed train" in the 13 th Five-Year Plan. As one of the most important processes in the manufacturing of high speed train bodies,welding has always been a symbol of high pollution and high energy consumption. As environmental requirements become more and more strict,the issue of solving the high pollution caused by welding has been imminent. A summary of the welding fume treatment technology was introduced in this article mainly from the points of the physical characteristics,the generation and dynamic changes of diffusion of the welding fume.关键词：welding fume;fume treatment;high speed train
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发布时间：2022-04-22 - 摘要：The influence of the precipitation on the accuracy of residual stress ultrasonic measurement was studied in this paper,the7 xxx aluminum alloy base material was kept warm for 2,4,6,8 hours at 200 degrees and then made into experimental samples. The stress constant K,propagation time of ultrasonic wave in zero stress medium t0 and ultrasonic attenuation of the samples were tested and the exact influence of the precipitation on two calculation parameters,K and t0 was analysed. After analysis,there were no significant changes of K,t0 and ultrasonic attenuation in the four groups of samples with obvious difference in precipitated phase content. This showed that the accuracy of residual stress ultrasonic measurement was not affected by the precipitation of 7 xxx aluminum alloy.关键词：residual stress;precipitation;stress constant;ultrasonic attenuation
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发布时间：2022-04-22 - 摘要：In this paper,friction stir welding（FSW） was applied to join 6005 A-T6 aluminum alloy side wall profiles. By using macroscopic metallurgical analysis,tensile tests and bending tests,optimal welding parameters were identified:spindle speed 800 r/min,welding speed 1000 mm/min,axial force 14.5 k N,shoulder plunge depth 0 mm. For a certain spindle speed and welding speed,axial force and shoulder plunger depth had less effects on the tensile and bending properties of joints. The axial force should be controlled critically. Overhigh axial force led to friction tool press down excessively,which damaged the base metal. The axial force being too low induced tunnel defects due to the insufficient stirring in base metal. As the shoulder plunger depth increased,flashes became easy to form.关键词：FSW;6005A-T6;side wall;weld defects
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发布时间：2022-04-22 - 摘要：the fatigue life of gearbox on bogie frame was simulated and calculated,the simulation conditions were the influence of residual stress was taken into account and the residual stress was not taken into account,and the simulation results were verified by fatigue test. The results showed that the weld on the back of the inner cavity of the gearbox hanger bracket is not a critical weld,which has little effect on the fatigue life of the hanger bracket. After 1 ×107 cycles,no cracks were found after magnetic particle inspection and liquid penetrant inspection.关键词：bogie;fatigue life;simulation;residual stress
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发布时间：2022-04-22 - 摘要：The technical features and the development of Friction Stir Welding（FSW） were introduced in this paper. A thick FSW joint structure was illustrated for a car coupler panel structure of the high speed train. The mechanical property,fatigue property,bending property and metallographic structure of the FSW joints were compared with those of the double V-groove MIG butt joints in order to validate the properties of its welded joints. The results showed that the FSW joints had better performance than the MIG joints. The FSW can be used in the manufacture of the high speed train and the further research direction is also be proposed.关键词：FSW;aluminum alloy carbody;welded joints
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发布时间：2022-04-22 - 摘要：TIG arc remelting treatment technology was used in the frame manufacture of high speed EMU bogies in this paper. It can effectively reduce the stress concentration caused by the abrupt change of geometry and can eliminate the defects such as undercut and groove. This technology can improve the fatigue performance of bogies and improve the safety performance and service life.关键词：TIG arc remelting;the composite processing;bogie;high speed EMU
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发布时间：2022-04-22 - 摘要：The end wall is an important part of the aluminum alloy car body in High-speed EMU. It has a complex construction,amount of accessories and large quantity of welding,all of which may induce the large welding deformation. Welding deformation is caused by uneven heating and cooling during welding. However,the deformation of aluminum alloy is large,which affects the manufacture and performance of welded structure. In this paper,the end wall of a standard EMU is taken as the research object,by adopting the appropriate tooling optimization,assembly process and reasonable welding sequence in the production and manufacture of the end wall,its welding deformation was well controlled,and so its flatness and profile. This reduced the intensity of working adjustment on end wall,improved production efficiency,and met the requirement of mass production. Moreover,the control method in this paper has a good reference significance for other EMU end wall manufacture,and has good value in popularizing.关键词：end wall;welding deformation;assembly process;welding sequence
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发布时间：2022-04-22 - 摘要：In this paper,the mechanical properties of SUS301 L series high strength austenitic stainless steel materials used for rail vehicles are analyzed. The welding performance of thin plate stainless steel used for vehicle is analyzed,especially the analysis of the welding performance under the special requirements of the surface coated rail car for the welding surface molding. It is suitable for the technology of resistance spot welding. The characteristics of the welding technology of the key parts of the stainless steel rail vehicle and the special external quality requirements of the non coated vehicles are analyzed. Analysis of vehicle welding using resistance spot welding equipment in spot welding equipment welding, welding equipment,welding equipment,appearance structure,ability of equipment basic operation,equipment and other aspects of the characteristics and requirements of the application requirements,summarizes and analyzes the resistance spot welding equipment used in stainless steel welding technology on vehicle.关键词：spot welding equipment;stainless steel vehicle;SUS301L
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发布时间：2022-04-22 - 摘要：To solve the cracking problem of the side apron plate generated in the underframe manufacture process of "Fuxing" EMU,the possible causes were analyzed. The primary and secondary causes of the cracking were confirmed by analysis.The structural design problem is the primary reason and the improper operation during the side apron plate installation process is the secondary reason. For those reasons,the welding procedure of the apron plate had been optimized and the quality of the weld had been increased. The bearing capacity of the weld had been increased 50% in theory. It is also concluded that the effective joint penetration should not be less than 3 mm in the aluminum alloy sheet welded structure,and complete penetration welding process should be used to ensure the bearing capacity of the welds.关键词："Fuxing" EMU;aluminum carbody;welding crack;process optimization
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发布时间：2022-04-22 - 摘要：In case of vertical sidewall of aluminum high-speed train,overall welding workpieces are analyzed whose flatness and vertical degree cannot meet the requirements. The workpieces can be qualified after mechanical adjustment and fire adjustment for several times. While welding deformation of workpieces who use a variety of controlling methods can be controlled effectively thus meeting the requirements without adjustment or little. This method can not only improve the product quality and production efficiency but also reduce waste emission. Guidance can be provided for production of other workpieces.关键词：vertical;flatness;vertical degree;welding deformation
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发布时间：2022-04-22 - 摘要：The welding test was conducted or carried out on one profile component of one railway vehicle,and the results were measured and analyzed. The effect of size precision,the quality of assembling,the strength of tack welding and the profile section on the linear misalignment in the process of welding of aluminum alloy profiles for railway vehicles were synthetically discussed,at the same time,the reasonable profile section was proposed,which can effectively avoid the generation probability of linear misalignment and improve the welding quality and the production efficiency.关键词：linear misalignment;aluminum alloy;profile section;railway vehicle
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发布时间：2022-04-22 - 摘要：In this paper, the causes of the incompletely filled groove of the butt welds in the fully mechanized welded underframe of the standard EMU at a speed of 350 km per hour were analyzed from the aspects of design structure and technological methods. In the aspects of design structure,intermittent welding technology,welding sequence,welding process parameters and so on,an optimization program has been developed and implemented in the project to completely solve the problem of incompletely filled groove during fully mechanized welding. As a result,weld repair amount dropped observably,which greatly improved the flatness after welding improved greatly,effectively reduce the work amount,suitable for mass production of plug-in aluminum alloy underframe to be fully mechanized welded.关键词：plug-in;aluminum alloy underframe;fully mechanized welding;incompletely filled groove;process optimization
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发布时间：2022-04-22 - 摘要：In the rail vehicle industry,resistance spot welding is mainly used to weld stainless steel carbody structure whose thickness is less than 5 mm. However,in the stainless steel body structure,the thickness of the bottom frame side beam and the reinforcing beam plate are both 6 mm. It is of practical significance if resistance spot welding can be used to reduce the welding distortion. Double sided single point resistance spot welding for SUS301 L-DLT stainless steel of 6 mm is carried out. The resistance spot welding process is determined through appearance test,smoothness test,section test and tensile shear test. The results show that under the reasonable parameter conditions,the nugget diameter of SUS301 L-DLT stainless steel of 6 mm can reach to φ12.2 mm,and the results of tensile shear test meet standard requirements. The increasing of electrode pressure can effectively avoid the appearance of shrinkage defects.However,the electrode pressure should not be too large,otherwise it may easily cause indentation too deep and nugget diameter too short.关键词：resistance spot welding;SUS301L-DLT stainless steel;shrinkage
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发布时间：2022-04-22 - 摘要：The strength of laser overlap laser welding joint of the column and the side wall of stainless steel railway vehicle body is higher than that of resistant spot welding joint,the frature forms of the two welding methods are different in the fatigue test. From a mechanical point of view,this may be related to the different stress distribution and the stress concentration of the two joints. And the stress concentration is the main factor causing the fatigue damage of welded joints. Therefore,based on the ABAQUS finite element analysis software,the stress distribution of the two kinds of joints under different applied loads is numerically analyzed,the stress concentration factor is calculated,and the initiation and propagation of fatigue cracks are predicted. The results show that the stress concentration factor of resistance spot welded joint is 4.42 times higher than that of laser welded joints,and 2.76 times higher than that of laser welded joints on one side of the column. The fatigue crack initiation position is at the maximum stress concentration,consistent with the simulation results.关键词：thin stainless steel plate;laser overlap welding;stress distribution;resistance spot welding
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发布时间：2022-04-22 - 摘要：Modern rail electrification need stable and reliable rectification power supply with high efficiency and high powder,and a lot of harmonic caused by the rectification power supply will result in grid-side low power factor operation and grid-side current waveform distortion. Based on this,the circuit topology structure and mathematical model of the single-phase voltage PWM rectifier were analyzed by using an indirect control method based on the phase and amplitude control-PAC strategy in this paper. The method was to control the amplitude and phase of the fundamental component of the bridge side alternating voltage,and thus the grid-side current was indirect controlled. The simulation verified the grid-side power factor of the control strategy was over 0.99,and the gridside current THD is less than 5%,which can meet the requirements of dual energy flow and adjustable output voltage.关键词：PWM rectification;power factor;PAC control
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发布时间：2022-04-22 - 摘要：The number of turns of the secondary winding of the transformer will increase when the conventional high-voltage output power supply is boosted by a transformer,resulting in the charging and discharging current and noise during working hours,and the energy loss of the primary side and secondary side of the transformer as well. In order to solve this problem,the power electronics technology and voltagedoubling rectification method were used to analysis two common voltage-doubling rectification circuits,the half-wave voltage-doubling rectification and the Schenkel voltage-doubling rectification. The characteristics of the two voltage-doubling rectification circuits were compared by the simulation and analysis. Compared with the half-wave voltage-doubling rectification circuit,the Schenkel voltage-doubling rectification circuit had a much smaller output ripple voltage,a shorter output voltage setup time and a higher output voltage.关键词：voltage doubler rectifier;circuit design;modeling and simulation
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发布时间：2022-04-22 - 摘要：<正>焊协（2018）秘字第004号焊接界同仁:"2018’中国焊接产业论坛——机器人焊接技术及应用"将于2018年5月5～7日在珠海召开。本次会议由中国焊接协会主办,中国机械工程学会为指导单位,德国焊接学会、美国焊接学会、新加坡焊接学会、中国机械工程学会焊接分会、中国电器工业协会电焊机分会、北京工业大学和上海交通大学协办,华南理工大学和中国焊接协会焊接设备分会承办,珠海市焊接协会、珠海市福尼斯焊接技术有限公
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发布时间：2022-04-22 - 摘要：<正>中电协焊机字[2018]3号各电焊机制造企业:行业统计工作是国家授予行业协会的行业统计职能,是政府交办的行业统计任务,同时也为行业企业经营决策提供服务。为了全面掌握我国电焊机行业的现状,电焊机分会根据中国机械工业联合会、中国电器工业协会及政府有关部门的要求,现开展"2017年度电焊机行业经济运行分析与数据统
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发布时间：2022-04-22 - 摘要：<正>各位作者:为确保杂志质量,尊重和保护作者和他人知识产权、著作权,根据国家期刊出版管理的相关规定,《电焊机》杂志特作以下申明。1.作者应保证是向本刊所投稿件的著作权人,不得抄袭、剽窃、盗用他人科研成果、文章和信息。文章中引用和参考他人文章、著作和成果（包括网络信息）时,按编辑出版规定,应在文章中以参考文献方式明确标识。如作者的文章涉及侵犯他人知识产权、著作权等合法权益时,一切后果文责自负。2.作者所投稿件应保证尚未在其他媒体（包括网络）出版或发表,也未向其他媒体投稿。
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发布时间：2022-04-22 - 摘要：<正>时光荏苒,中国汽车工业的发展已经有60多年的历史。汽车工业正朝着环保低碳、节省能源、安全性、舒适性和车身轻量化方向发展。焊接是汽车制造业中必不可少的环节,汽车产品的车型众多、成形结构复杂、零部件生产专业化、标准化以及汽车制造在质量、效率和成本等方面的综合要求,都决定了汽车焊接是一个多学科、跨领域和技术集成性强的生产过程。加强焊接技术的科学化操作势在必行,研发出更可靠的焊接技术能够使汽车整体质量得到大幅度的提升。
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发布时间：2022-04-22 - 摘要：<正>书号:0163售价:46元本书对易于实现自动化和智能化生产的气体保护焊技术及工程中的应用作了简明地阐述,力求突出先进性和实用性特色。本书主要针对工程中最常见的惰性气体保护焊（TIG、MIG）、活性气体保护焊（CO2焊、MAG）、等离子弧焊（PAW）等焊接方法,突出了各种气体保护焊的工艺特点和应用。给出了具体的工艺参数、相关技术数据及针对一些典型工程结构产品的应用实例,可以指导焊接生产。本书内容选用了一些便于实现自动化焊接的先进的气体保护焊工艺
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发布时间：2022-04-22 - 摘要：<正>《电焊机》杂志是中国科技论文统计源期刊（中国科技核心期刊）、《中文核心期刊数据库》收录期刊、"英国《科学文摘》（INSPEC）来源期刊""俄罗斯《文摘杂志》收录期刊""美国《剑桥科学文摘》（CSA）收录期刊""波兰《哥白尼索引》（IC）"收录期刊等。各地邮局均可订阅,邮发代号:62-81,订价:15元/月,180元/年。
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发布时间：2022-04-22 - 摘要：<正>随着交通运输、航空航天、海洋工程、军事、核能等快速发展,材料发生了极大的变化,高强超高强钢、高强铝合金、镁合金、不锈钢、大厚钢板等日益普及,成分及性能高品质焊缝要求、高效和智能焊接已然是焊接的新常态,传统单一热源已面临着高质高效焊接无法解决的窘境。近年,由此催生的焊接复合热源,通过两种或两种以上单一焊接方法的复合,取其所长,形成了新的更为先进的焊接方法,已从电弧物理基础、电源特性、焊接工艺、装备集成等方面取得了重大进展,焊接材料原位复合上也成绩喜人,在
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发布时间：2022-04-22 - 摘要：<正>书号:0023售价:58.00元本书介绍了逆变式弧焊机相关的基本电路、功率器件、高频变压器设计及铁磁性材料、高频电容器、PWM集成控制电路、电流传感器、新型绝缘材料等基础知识,同时对逆变式弧焊机发展过程中存在的可靠性、节能、电磁兼容等一系列热点问题进行了探讨和论述,并通过对目前具有
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发布时间：2022-04-22 - 摘要：<正>书号:0226售价:38.00元本教材以焊接结构制造工艺过程为主线,全面论述焊接结构制造中的工艺规程编制、备料加工、装配焊接及装备、典型焊接结构的制造技术、质量控制与检测、焊接生产环保和安全等五大板块,共8章。本教材较全面地反映了焊接结构制造的新技术、新方法和新装备。本教材可作为普通
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发布时间：2022-04-22 - 摘要：<正>书号:0111定价:26元为配合技师评聘工作的开展,满足机械行业对工人技师培训和考评的需要,加快技师培训教材建设,我们经过到上海、江苏、四川等地进行广泛的调研,并结合《通知》精神,确立了教材编写的总体思路;组织了一批由工程技术人员、教师、技师、高级技师组成的编写队伍,编写了这套《机械工业技师考评培训教材》。全套
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发布时间：2022-04-22 - 摘要：<正>书号:0095定价:16元焊接操作中存在诸多危险因素和有害因素,可能发生触电、火灾、爆炸、灼烫和高处坠落等工伤事故,还可能患眼睛、皮肤、呼吸系统和血液等疾病。因此,焊接属于特种作业,电气焊工属于特殊工种,遵照国务院颁布的有关规定,焊工必须经过安全培训并考试合格,方准独立操作。并且在取得安全考核合格证之后,尚需定期参加复审。焊接安全与卫生防护的教学内容繁多,涉及的理论知识范围甚广,本书是根据国务院1963年
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发布时间：2022-04-22 - 摘要：<正>书号:230定价:34元本书是为满足普通高等教育"材料成型及控制工程"专业毕业后从事焊接技术工作的学生、材料加工工程专业焊接方向的研究生了解和掌握焊接专业基础知识,以及企业开展焊接工程师培训和焊接工程技术人员自学焊接专业基础知识的需要而编写的"焊接工程师系列教程"之一。主要内容有:焊接电弧的电特性和焊接工艺对弧焊电源的要求,弧焊电源的基本特性,弧焊变压器、弧焊整流器、弧焊逆变器、数字控制弧焊电源的基本原理、结构、性能特点及其应用,以及弧焊电
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发布时间：2022-04-22 - 摘要：<正>好书推荐,欲购从速!书号:0232定价:41元本书主要讲述如何控制焊接变形。内容包括焊接变形的规律和梁、柱焊接弯曲变形的计算,焊接板结构箱形梁腹板预拱度计算,减小焊接变形的方法,焊接变形的机械矫正方法、火焰矫正的机
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发布时间：2022-04-22
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