焊接方法对奥氏体不锈钢焊接接头低温冲击性能的影响OA北大核心CSTPCD

To investigate the impact of low temperature impact performance of austenitic stainless steel welded joint on the safety of low temperature pressure vessels.The effects of three welding methods,GTAW,GMAW and SAW,on the low temperature impact performance of S30408 and S31608 austenitic stainless steel joints were studied by low temperature impact test at-196℃.For S30408 welded joint,the low temperature impact performance parameter of the heat affected zone is smaller than that of the base metal and weld zone,which becomes the weak position.Among the three welding methods,the impact performance parameters of welded joint obtained by GTAW are at the optimal level in the heat affected zone.For the low temperature impact performance of S31608 welded joint,the difference between weld,heat affected zone and base metal is small.Among the three welding methods,the result of the welded joint by SAW is similar to that of the base metal in terms of impact absorption energy,and better comprehensive impact performance of the welded joint can be obtained.The comparison of fracture morphologies of welded joints under different welding processes shows that the impact fracture morphologies of welded joints in different regions are consistent with the results of low temperature impact parameters.The research work provides a reference for the selection of welding method of low temperature austenitic stainless steel pressure vessel.