针对深熔钨极氩弧焊接方法，研究其在8 mm厚316L不锈钢与Q345低合金钢连接上的应用，并采用ANSYS有限元软件模拟焊接过程，对焊接过程的稳定性进行评估。结果表明，一定焊接参数下，深熔TIG焊接8 mm厚度异种钢能达到单面焊双面成形，得到成形良好的焊缝。同时基于异种钢焊接试验结果提出一种非对称的热源模式，由上部分双椭球热源与下部分圆柱热源组合形成，热源各部分独立调节。非对称热源在模拟中的应用，得到与实际焊缝吻合度更高的结果，平均误差不超过8%；模拟结果显示，316L不锈钢侧温度较低，其窄的背面焊道宽度和高表面张力，弥补Q345侧的不足，使得小孔平衡，维持焊接过程的稳定进行。
A research of the welding process of the 8mm thickness 316L stainless steel and Q345 low alloy steel is conducted using key-hole tungsten inert-gas welding. ANSYS finite element software is used to simulate the welding process and evaluate the stability of the welding process. The results show that under certain welding parameters, a well formed weld with sided welding double-sided forming can achieved by keyhole TIG welding of dissimilar steel. At the same time, an asymmetric heat source model is proposed based on the results of dissimilar steel welding. The upper part of the double ellipsoid heat source is combined with the lower part of the cylindrical heat source, and the heat source is adjusted independently. The application of asymmetric heat source results in a high degree of coincidence with the experimental weld, with an average error of no more than 8%. The simulation results show that, temperature in the 316L stainless steel side is lower, and the narrow root weld bead width and high surface tension in 316L stainless steel side make up for the defect of Q345 side, causing the keyhole balanced and maintaining the stability of the welding process.
[1] 李增荣. Q235钢与1Cr18Ni9Ti不锈钢异种钢焊接接头性能的研究[J]. 中国新技术新产品,2012(21):21. LI Zengrong. Study on the performance of Q235 steel and 1Cr18Ni9Ti stainless steel dissimilar steel welded joints[J]. China New Technologies and New Products,2012(21):21.
[2] 蔡建鹏,叶延洪,张彦杰,等. 坡口形式对Q345/SUS304异种钢对接接头残余应力和变形的影响[J]. 机械工程学报,2015,51(10):55-61. CAI Jianpeng,YE Yanhong,ZHANG Yanjie,et al. Study on influences of groove type on welding residual stress and deformation in Q345/SUS304 dissimilar steel butt-welded joints[J]. Journal of Mechanical Engineering,2015,51(10):55-61.
[3] 李克俭,蔡志鹏,李轶非,等. 碳迁移对9%Cr和2.25%Cr异种钢焊接接头高温韧性的影响[J]. 机械工程学报,2015,51(16):150-155. LI Kejian,CAI Zhipeng,LI Yifei,et al. Influence of carbon migration on the toughness of heat affected zone of 9%Cr+2.25%Cr dissimilar welds at high temperature[J]. Journal of Mechanical Engineering,2015,51(16):150-155.
[4] 张瑞华,栗海霞,李明,等. K-TIG焊接电弧特性的数值分析[J]. 电焊机,2013,42(12):7-11. ZHANG Ruihua,LI Haixia,LI Ming,et al. Numerical analysis on keyhole gas tungsten arc welding[J]. Electric Welding Machine,2013,42(12):7-11.
[5] FENG Y,LUO Z,LIU Z,et al. Keyhole gas tungsten arc welding of AISI 316L stainless steel[J]. Materials & Design,2015,85:24-31.
[6] 樊文飞,罗震,冯悦峤,等. 低合金钢Q345的深熔TIG焊研究[J]. 上海交通大学学报,2016(S1):102-105. FAN Wenfei,LUO Zhen,FENG Yueqiao,et al. Study on the deep penetration TIG welding of Q345 steel[J]. Journal of Shanghai Jiaotong University,2016(S1):102-105.
[7] LATHABAI S,JAVRIVS B L,BARTON K J. Comparison of keyhole and conventional gas tungsten arc welds in commercially pure titanium[J]. Materials Science and Engineering:A,2001,299(1):81-93.
[8] 冯悦峤. 中厚钢板的深熔TIG焊工艺研究及温度场数值模拟[D]. 天津:天津大学,2016. FENG Yueqiao. Process investigation and temperature filed simulation on deep penetration TIG welding of mid-thickness steel[D]. Tianjin:Tianjin University,2016.
[9] 潘家祯. 压力容器材料实用手册[M]. 北京:化学工业出版社,2000. PAN Jiazhen. Practical handbook for pressure vessel materials[M]. Beijing:Chemical Industry Press,2000.
[10] 李慧娟. 厚板多层多道焊的有限元数值模拟分析[D]. 天津:天津大学,2007. LI Huijuan. Finite element numerical simulation analysis of multi-layer multi-pass welding of thick plate[D]. Tianjin:Tianjin University,2007.
[11] 胡庆贤. 穿孔等离子弧焊接温度场的有限元分析[D]. 济南:山东大学,2007. HU Qingxian. Finite element analysis of temperature field in perforated plasma arc welding[D]. Jinan:Shandong University,2007.
[12] EISAZADEH H,BUNN J,AIDUN D K. Numerical and experimental investigation of residual stress distribution in a dissimilar ferritic-austenitic weld[J]. Welding Journal,2017,96(1):21-30.
