最新刊期
期 3 ， 2019
- 摘要：Friction stir welding of 10 mm T2 cooper with different process parameters were studied in this paper. The results showed that the defect-free sound joints with good surface forming can be achieved with in certain ranges of process parameters. The weld cross-section consists of weld nugget zone,heat affect zone and base metal,the thermo-mechanically affected zone was not found.Significant dynamic recrystallization occurred in the weld nugget zone and fine equiaxed crystal structures were obtained. The grain size in heat affect zone increased a little. The distribution of microhardness at cross-section was "W" shape. the microhardness values of stir zone and heat affected zone were lower than base metal the lowest microhardness occurred in heat affect zone,the microhardness in weld nugget zone were relative stable. The tensile strength of the joint reached 97% of the base metal,when the rotation speed was 400 r/min and the welding speed was 100 mm/min. The fracture positions of joints under different parameters were at the retreating side of the heat affected zone.关键词：T2 cooper;friction stir welding;microstructure;mechanical properties
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发布时间：2022-03-15 - 摘要：The tendency of welding cracks of X80 steel involved in the slit type cracking test was discussed. The results show that the section crack rate of X80 pipeline steel decreases with the increase of the preheating temperature of the workpiece,the shape and nature of cracks that are cracked at the root stress concentration and distributed along the fusion zone are hydrogen-induced cold cracks. The area has become the weak link of the joint when the cold crack three factors are focused on the coarse-grained zone of the fusion zone of X80 pipeline steel,so it is easy to form cracks on the area. The microstructure characteristics of fusion zone are the necessary condition of the cracks to form in the influencing factors,the stress level and distribution characteristics of hydrogen are sufficient conditions. The relationship between the welding process and cracking essentially reflects the relationship between hydrogen,stress and crack in weld metal. The comprehensive processes of low hydrogenation with minimizing residual diffusion hydrogen in the weld metal and insufficient to cause hydrogen-induced cold cracks are often used in engineering,and have achieved satisfactory results.关键词：welding crack;X80 steel;slit type cracking test;diffusion hydrogen;low hydrogen process
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发布时间：2022-03-15 - 摘要：The Box-Behnken response surface analysis method was used to optimize the surface morphology of the laser tailor-welding.The four factors,welding voltage,pulse frequency,pulse width,speed of welding,were selected for experimental design. The secondary response surface model was obtained. The response surface analysis show that the welding pressure and pulse frequency have a great influence on the morphology of the weld,followed by the welding speed and pulse width. Through optimization,it is found that when the welding voltage,pulse frequency,pulse width and welding speed are 265.42 V,19.65 Hz,10.22 ms,and 321.26 mm/min,respectively,the weld morphology is best. Moreover,the F value is 5.51 obtained by the model variance,indicating that the quadratic equation is significant. The model fitted well in the entire regression region,which could be used to analyze and predict the process of the weld morphology. Through the experimental comparison and analysis,it is found that the welding morphology,microstructure and hardness values are better under the optimal process parameters.关键词：response surface methodology;laser tailor-welding;DP600;process parameters;property
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发布时间：2022-03-15 - 摘要：Because aluminum and magnesium alloys,which have been widely used in aerospace and electronics,are difficult to achieve ultra-thin plate welding,a micro friction stir welding machine based on Mach3 control system was designed. For the welding operation using this equipment,the stirrer with a shoulder that diameter was 6～8 mm could be used for the welding of thin plates（≤1 mm）,and the 3 D forming micro friction stir welding could be completed. There was a small amount of heat input in the welding process,small deformation occurred and the appearance of weld was great. The Mach3 control system is excellently compatible,applicative,and stable.It is easy to operate,maintain and open. The micro friction stir welding machine is small in size,light in weight and easy to install. The welding machine is available with high welding stability and operability.关键词：friction stir welding machine;control system;micro-jointing;3D forming
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发布时间：2022-03-15 - 摘要：Based on the structural characteristics of the frame products of Pakistan railway train,this paper analyses and cracks the difficulties in the internal inspection technology of the girth weld of the cross-side beam interface of Pakistan railway train. The phased array ultrasonic testing technology scheme is established through experiments. The phased array ultrasonic testing of the girth weld of the cross-side beam interface of the frame can accurately detect the various types of internal defects in girth weld,full coverage of weld seam and detection of various internal defects are realized. The interference of structure can be eliminated according to the echo image display. It not only ensures the quality of weld seam,but also improves the production efficiency,and achieves satisfactory results. The application of phased array ultrasonic technology in girth weld detection is studied,which has been verified in practical testing.关键词：circumferential weld seam;phased array ultrasonic;frame;defect
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发布时间：2022-03-15 - 摘要：09MnNiDR low-temperature steel is utilized for building and installing container. In practice,the container is sometimes required to perform two or more post weld treatment（PWHT）. This PWHT leads to the deterioration of welded joint properties,especially impact toughness at lower temperature. In this present work,The effects of different heat treatment temperatures of 545 ℃,570 ℃,600 ℃and duration time on strength and impact toughness of welded joint were studied. Three heat treatment temperatures were selected according to the installation site and condition. The result reveals that 545～600 ℃ is applicable PWHT temperature for 09MnNiDR lowtemperature steel. When PWHT times are more than twice,the proper PWHT temperature is 545～570 ℃.关键词：low-temperature steel;post weld heat treatment;impact toughness
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发布时间：2022-03-15 - 摘要：The welding of 7 200 KW electric locomotive body bolster pillow-waist barrel changes from manual welding to IGM welding manipulator welding,based on the structure and technology analysis,the welding technology using IGM welding manipulator is developed and implemented. The results show that by controlling the size of workpiece assembly,adjusting the welding parameters and the number of welding layers,and improving the programming of welding manipulator, the IGM welding manipulator with rich argon gas shielded welding not only can completely meet the design requirements of the structure to ensure the quality,but also greatly improve the welding efficiency.关键词：IIGM welding manipulator;body bolster pillow-waist barrel;backing weld;welding programming
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发布时间：2022-03-15 - 摘要：Under the programming environment of LabVIEW,a set of arc welding parameters measurement and control system is developed by using NI USB-6215 multi-function data acquisition card,which can control the output of DC,pulse,sinusoidal wave and other required waveforms. Meanwhile,current and voltage signals in the welding process can be collected and saved,and their waveforms can be displayed in real time. The saved signal can be played back and analyzed by filtering,statistics,UI and so on. The system provides a more intuitional basis for analyzing the entire welding process,realizing waveform control and energy control,and is beneficial to the technology testing and optimization of the welding process.关键词：data acquisition;arc welding;LabVIEW;waveform control
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发布时间：2022-03-15 - 摘要：The automatic welding production of the front wheel cover assemblies of the auto parts and the longitudinal beam assemblies of the rear floor is taken as examples to introduce the design ideas of the spot welding robot workstation in detail,including the technical requirements,composition and characteristics,and electrical control system, etc. The working principle of the safety system,welding fixture system and water & gas system are emphatically analyzed. The service condition of the spot welding robot workstation is also introduced briefly. Practice proves that the four spot welding robot workstations designed are easy to operate,and have good welding quality and high production efficiency,also can completely meet the requirements of automatic welding of the front wheel cover assemblies and rear floor longitudinal beam assemblies. The design concept of this spot welding robot workstation has certain reference for the design and application of robot workstation and automatic production line.关键词：spot welding robot workstation;design;automatic welding;auto parts
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发布时间：2022-03-15 - 摘要：The Bantam-Fan 1500 gas shielded welding machine is the Fronius brand from Austrian and sold by Yantai Pentium company,which is used in national vocational colleges auto body repair（sheet metal） skills competition. But some functional faults occur in use that can not be repaired in China,which brings great inconvenience to the competition. Through research and practice in the process of use,the structure and working principle of this machine are mastered,and the fault phenomena are sorted,including no reaction when pulling gun trigger,severe sputtering and weld porosity,no arc but wire feed motor work,arc without pulling gun trigger.The main causes for the faults are analyzed,and the corresponding maintenance and use precautions are summarized.关键词：V1500 welding machine;skills competition;fault;maintenance
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发布时间：2022-03-15 - 摘要：A monitoring system of welding equipment based on Internet of things（IOT）technology is proposed,which realizes the data acquisition and monitoring of welding equipment and remote control of welding equipment. This system framework takes Renesas MCU as the controller,IOT technology as the core,and cloud platform as the basis,realizes the data transmission and control between the welding equipment and the cloud platform,and improves the precision management of welding process. The experimental results show that this system is stable in operation,reliable in data transmission,and is suitable for various welding occasions.关键词：IOT;internet of things;welding equipment;cloud platform
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发布时间：2022-03-15 - 摘要：The technology of automatic welding technology for long-distance pipeline has been widely used in long-distance pipeline welding as its fast welding speed,small groove angle and narrow welding surface. However,during the process of radiographic inspection（RT）welding seam,it is always puzzled by the linear images which are often mistaken for false defects. In this paper,carry out process evaluation tests and take comparison of unqualified RT samples. Finally,find that this kind of linear image is not a pseudo-defect,but a linear defect produced by edge incomplete fusion. According to the causes of the defect,we find out the solution to eliminate edge incomplete fusion,and improve the quality of long-distance pipeline automatic welding. The welding qualification rate can reach more than 98.5% by one pass welding.关键词：long-distance pipeline;automatic welding;edge incomplete fusion;pseudo-defect
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发布时间：2022-03-15 - 摘要：In order to study the initiation and propagation of weld structure cracks,four different weld toe chamfer weld cross joint models were established by using abaqus software. The extended finite element method（XFEM）was used without pre-set cracks. The type is set to the plane stress state and the plane strain state,respectively,and then the crack initiation expansion simulation is performed. The results show that the crack is more likely to sprout and expand under the plane strain state,and the weld toe chamfer has an influence on the crack initiation position and the extension path.关键词：welded structure;XFEM;crack initiation;crack propagation;cross joint
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发布时间：2022-03-15 - 摘要：High-rotation speed friction stir welding machine and water mist cooling device were designed. The experimental result shows that the butt welding test of 1 mm 6061-T6 sheet aluminum alloy was carried out successfully. Under the condition of highrotation speed and small plunge depth（0.08 mm）,the forward force increases with the increase of rotation speed and the welding speed,and the maximum value is not more than 70 N. The relationship between side force and welding speed and rotational speed is not obvious,and its maximum value is not more than 60 N. The axial force increases with the increase of shoulder width,but decreases with the increase of pin length,and its maximum value is not more than 2.5 kN. The tensile strength of the joint was 265 MPa which come to87.2% of the base metal,when the rotation speed was 15 000 r/min and the welding speed was 100 mm/min.关键词：high rotation speed friction stir welding machine;water mist cooling device;6061-T6 sheet aluminum alloy;welding process parameters
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发布时间：2022-03-15 - 摘要：n this paper,the effects of high cycle alternating stress loading on mechanical properties and microstructures of overlap joints of 6005 A aluminium alloy profile by MIG welding with pre-accelerated test were studied. The results show that the average tensile strength of the specimens without accelerated test is 204.836 3 MPa. The average tensile strength of the specimens with 60% fatigue limit accelerated test is 204.028 2 MPa and the fracture location is HAZ. The average tensile strength of the specimens with 90% fatigue limit accelerated test is 188.701 6 MPa;and the weld of the specimens without accelerated fatigue limit accelerated test is 188.701 6 Ma. The average hardness of the core is 69.30 HV,the average hardness of the weld center of 60% accelerated fatigue specimens is70.07 HV,and the average hardness of the weld center of 90% fatigue specimens is 66.45 HV. The average impact energy of the samples without accelerated test and 60% fatigue limit accelerated test is 6.67 J,and that of the samples with 90% fatigue limit accelerated test is 6 J. The reason for the change of properties lies in the change of grain size and morphology. When the load is higher in accelerated test,the grain of welded joint is elongated,resulting in coalescence,the decrease of grain boundary area and the decrease of grain boundary energy storage.关键词：6005A;MIG;fatigue acceleration;mechanical properties;microstructure
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发布时间：2022-03-15 - 摘要：The structures of bogies are complex and the welds distributed densely and the numbers are lot for the high speed trains. The medium plate welding of frames with ultra narrow gap wire filling laser welding technology can solve the problem of multiple passes,large deformation and residual stress of traditional MAG welding,and it can also solve the problem of the sensitivity of groove clearance of laser welding. This paper is focused on the molten drop transition of ultra narrow gap wire filling laser welding. The results showed that the transition mode of molten drop was first unfold transition and then liquid bridge transition and finally particle transition when the laser wire spacing was different. The transition mode of molten drop changed from unfold transition under lower power to liquid bridge transition under higher power. The welding speed didn’t affect the transition mode and still the liquid bridge transition. The feeding speed would affect the molten period of the wire and then produce different molten transition mode. It should choose negative defocus when welding thick plate and should choose positive defocus when welding thin plate.关键词：bogies frame;ultra narrow gap wire filling laser welding;molten drop transition
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发布时间：2022-03-15 - 摘要：Local echo equivalent is found out of limits in an ultrasonic flaw detection of 60 kg/m U75 V rail welded joints in a rail welding plant,while the drop hammer test results of the joint are qualified. To explore the causes,the fractures after repeated drop hammer tests are analyzed by optical and electron microscopy and energy disperse spectrometer. The results show that: grey spots on the fracture surface are the main reason for excessive local echo equivalent of ultrasonic wave,and the two grey spots are caused by slag residue in rails and silicate inclusions not being extruded during welding respectively. It is suggested that the welding parameters setting should be further optimized关键词：flash welding;fracture;gray spot
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发布时间：2022-03-15 - 摘要：The application of electrolytic corrosion in the macrographic examination for stainless steel welding joints is studied,the corrosion solution,corrosion time and output current are selected by experiments. The results show that after being corroded in the corrosion solution consisting of 10 ml nitric acid and 90 ml water for 6 minutes at room temperature with output current of 2 A,a clear macroscopic morphology specimen of stainless steel welding joint is prepared,and the each regions of welding joints can be clearly displayed.关键词：stainless steel;welding joints;macrographic examination;electrolytic corrosion
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发布时间：2022-03-15 - 摘要：The arc behavior of cold metal transfer technology in welding process and its effect on the appearance of weld are studied in details,and the micro-mechanism is also analyzed. The welding parameters such as welding voltage,welding current,wire feed rate and so on is controlled through integrated precision system,the micro-behavior of the welding arc are researched,the perfect combination of metal transfer physical behavior and welding parameters is achieved,which provides the theoretical base for obtaining high quality joining and appearance of welds,and also meets the design and welding demand for thin sheet covering parts of body-in-white. It has very important theoretical and practical engineering application value for enrichment and development of MIG welding method.关键词：cold metal transfer;arc behavior;appearance of weld
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发布时间：2022-03-15 - 摘要：Gas welding was usually used for welding of T2 copper and 304 stainless steel before. Because the product is used in high temperature, the welded joint is easy to loose when heating,the leakage is caused and joint strength reduces,some joints can not meet the requirements. After repeated tests,it is found that the argon arc welding is better than gas welding for welds of T2 copper and stainless steel. Argon arc welding is easy to operate and its welding quality is stable. It also can reduce manufacturing cost greatly,shorten production period and enhance the strength of joints.关键词：T2 copper;304 stainless steel;welding methods selection
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发布时间：2022-03-15 - 摘要：In order to study the effect of laser welding heat treatment process on the microstructure and properties of weld,pre-welding and post-welding heat treatment were established. Metallographic microscope and scanning electron microscope were used to observe and analyze the microstructure of the weld,and used HV0.1 microhardness tester to measure the hardness of the weld area. The results showed that by means of pre-welding and post-welding heat treatment, the ferrite in the metallographic structure increased obviously,while the pearlite was less and the hardness was lower,especially the post-welding heat treatment improved the microstructure and properties most significantly.关键词：welding process;preheating before welding;post-welding heat treatment;weld quality
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发布时间：2022-03-15 - 摘要：In the construction of gas interruption joint of natural gas pipeline,it is strictly forbidden to group welding joints by force.Construction workers often have doubts about this prohibition. They think that in the process of welding joint set alignment,as long as the welding joint can be aligned,non-destructive testing is qualified. Feeling forced group only increases the residual stress of the weld,and has little effect on the safe operation of the pipeline. Therefore,the simulated forced group welding test is carried out. Through the analysis of the theoretical data such as bending and impact of the qualified simulated weld specimens by conventional non-destructive testing,it is concluded that the hardness of the forced group welding joint increases and the toughness decreases,and it is easy to cause micro-cracks in the welding process,resulting in cracking failure after commissioning. It can not effectively satisfy the conclusion of safe operation of pipeline.关键词：stress weld;analysis;weld quality
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发布时间：2022-03-15 - 摘要：wo kinds of austenitic stainless steel sheet samples with three kinds of thickness are welded by TIG welding,the mechanical properties and microstructure of the weld joints are investigated. By visual inspection, there is no defect on the weld samples surface. All weld samples fracture at the base mental,while the strength and hardness of welded joint of 0Cr18Ni9 weld sample are higher than those of 1Cr18Ni9Ti weld sample,and the hardness distribution of 0Cr18Ni9 is more homogeneous. Owning to fine and homogeneous vermicular ferrite in joint microstructure,the mechanical properties of 0Cr18Ni9 is better than that of 1Cr18Ni9Ti whose joint microstructure contains coarse ferrite and austenitic.关键词：stainless steel;tensile strength;ferrite
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发布时间：2022-03-15 - 摘要：The welded joint of duplex stainless steel is got by FCAW. The influence of flux-cored component,metallographic structure and solution treatment on the corrosive property of welded joint are researched. The pitting process and influence factors of weld metal FeCl3 are detailed analyzed. The pitting formation mechanism of the weld microstructure is studied,which is good for the application of duplex stainless steel in welding process. When increasing the proportion of austenite phase by improving the content of nickel alone,the corrosion rate of welded joints is large,adding element nitrogen is an effective way to ensure a reasonable two-phase ratio. The results show that the distribution,proportion, form and solid solution treatment of two-phase microstructure have great influence on the corrosion property,and the uniform microstructure is helpful to improve the corrosion resistance of the weld metal. By analyzing the pitting process of weld metal, it is found that the defects on the surface of the sample, such as porosity or slag inclusion,are generally the source of pitting,which will accelerate the corrosion rate,and the technological performance of the welding wire directly affects the corrosion property of the joint.关键词：duplex stainless steel;welded joint;corrosive resistance property;flux-cored wire
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发布时间：2022-03-15 - 摘要：<正>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、火焰矫正的机理和火焰矫正的实际操作方法。本书适合于从
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发布时间：2022-03-15 - 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：2022-03-15 - 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：2022-03-15 - 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：2022-03-15 - 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"
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发布时间：2022-03-15
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