S690QL低合金高强钢焊接接头组织特征和低温韧性研究
Study on the Microstructure and Toughness of Welded Joint of S690QL Low-alloy High-strength Steel
- 2024年54卷第5期 页码:17-24
纸质出版日期: 2024-05-25
DOI: 10.7512/j.issn.1001-2303.2024.05.02
扫 描 看 全 文
浏览全部资源
扫码关注微信
纸质出版日期: 2024-05-25 ,
扫 描 看 全 文
王艳华,谢耿,张斌,等.S690QL低合金高强钢焊接接头组织特征和低温韧性研究[J].电焊机,2024,54(5):17-24.
WANG Yanhua, XIE Geng, ZHANG Bin, et al.Study on the Microstructure and Toughness of Welded Joint of S690QL Low-alloy High-strength Steel[J].Electric Welding Machine, 2024, 54(5): 17-24.
对40 mm厚S690QL高强钢进行多层多道焊接,观察焊缝金属和热影响区的显微组织特征,统计M-A组元数量和形貌,分别对母材、焊缝金属和热影响区进行了冲击韧性测试和断裂韧性测试。结果表明:多次热循环促进了碳元素的析出和偏聚,在焊缝金属和粗晶区均发现了M-A组元的存在,它们的含量分别为5.8%和12.5%,平均尺寸分别为0.157 μm和0.194 μm。粗晶区的M-A组元尺寸较大,且在原奥氏体晶界处呈链状分布。母材、焊缝金属和粗晶区的室温CTOD平均值分别为0.38 mm,0.25 mm和0.22 mm。粗晶区的力-位移曲线出现明显的局部陡降特征,表明粗大的M-A组元加速了裂纹扩展速率。焊缝金属和粗晶区的冲击吸收功均随温度下降而显著下降,表明M-A组元的脆化效应随温度下降而加剧。-40 ℃时,焊缝金属冲击吸收功急剧降低,与粗晶区接近,表明M-A组元对韧性的不利影响在低温时占主导地位。
The study involved the multi-layer and multi-pass welding of 40 mm thick S690QL high-strength steel. The research focused on observing the microstructure characteristics of the weld metal and heat affected zone
as well as counting the number and morphology of M-A constituents. Additionally
tests were conducted to evaluate the impact toughness and fracture toughness of the base metal
weld metal
and heat affected zone. The results revealed that multiple thermal cycles facilitated the precipitation and segregation of carbon elements. M-A constituents were present in both the weld metal and coarse crystal zone
with contents of 5.8% and 12.5% respectively. The average size of the M-A constituents was measured at 0.157 μm and 0.194 μm. In the coarse-grained zone
the M-A constituents exhibited a larger size and formed a chain-like distribution along the grain boundary of the prior austenite. The average CTOD values for the base metal
weld metal
and coarse crystal area were 0.38 mm
0.25 mm
and 0.22 mm respectively. Notably
the force-displacement curve of the coarse crystal zone demonstrated a significant localized steep drop
indicating an accelerated crack growth rate due to the presence of coarse M-A constituents. Furthermore
the impact absorption energy of both the weld metal and coarse crystal zone exhibited a significant decrease with decreasing temperature
suggesting an increased embrittlement effect of the M-A constituents at lower temperatures. At -40 ℃
the impact absorption energy of the weld metal sharply decreased
close to the CGHAZ
indicating that the adverse effect of M-A constituents on toughness dominated at low temperatures.
高强钢M-A组元粗晶区冲击韧性断裂韧性
high-strength steelM-A constituentsCGHAZimpact toughnessfracture toughness
Zhang Y,Xiao J,Liu W,et al. Effect of welding peak temperature on microstructure and impact toughness of heat-affected zone of Q690 high strength bridge steel[J]. Materials, 2021, 14, 2981.
Gáspár M. Effect of welding heat input on simulated HAZ areas in S690QL high strength steel[J]. Metals, 2019,9:1-14.
Lan L,Qiu C,Zhao D,et al. Microstructural characteristics and toughness of the simulated coarse grained heat affected zone of high strength low carbon bainitic steel[J]. Materials Science & Engineering A, 2011, 529: 192-200.
Chen C X,Li W S,Peng H F. Investigation on M-A Constituent in Weld CGHAZ of High-Strength Microalloyed Steel[J]. Materials Science Forum,2008,575-578: 690-695.
Bonnevie E,Ferriere G,Ikhlef A,et al. Morphological aspects of martensite-austenite constituents in intercritical and coarse grain heat affected zones of structural steels[J]. Materials Science & Engineering A,2004,385:352-358.
Ramachandran D C,Moon J,Lee C H,et al. Role of bainitic microstructures with M-A constituent on the toughness of an HSLA steel for seismic resistant structural applications[J]. Materials Science & Engineering A,2021,801:140390.
Wang X L,Wang Z Q,Xie Z J,et al. Toughening coarse grained heat affected zone of high strength offshore engineering steel by enhancing the completeness of austenite-bainite transformation[J]. Materials Letters,2019,257:126727.
Tian Y,Li Q,Wang Z,et al. Effects of ultra-fast cooling on microstructure and mechanical properties of pipeline steels[J]. Journal of Materials Engineering and Performance, 2015, 24(9): 3307-3314.
Lan L Y,Qiu C L,Song H Y,et al. Correlation of martensite-austenite constituent and cleavage crack initiation in welding heat affected zone of low carbon bainitic steel[J]. Materials Letters,2014,125:86-88.
Luo X,Chen X H,Wang T,et al. Effect of morphologies of martensite-austenite constituents on impact toughness in intercritically reheated coarse-grained heat-affected zone of HSLA steel[J]. Materials Science & Engineering A,2018,710:192-199.
Li X,Shang C,Ma X,et al. Structure and crystallography of martensite-austenite constituent in the intercritically reheated coarse-grained heat affected zone of a high strength pipeline steel[J]. Materials Characterization,2018,138:107-112.
编辑部网址:http://www.71dhj.comhttp://www.71dhj.com
相关作者
相关机构