基于高强高韧焊丝的脉冲GMAW焊缝金属强韧化机理研究  

Strengthening and Toughening Mechanism of Weld Metals on GMAW-P of High Strength and High Toughness Welding Wire

作　　者：崔桂涵 杨春利[1] CUI Guihan;YANG Chunli(State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001)

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《机械工程学报》2024年第4期326-334,共9页Journal of Mechanical Engineering

摘　　要：采用新型高强高韧钢焊丝对10Ni5Cr Mo V钢进行脉冲气体保护焊接,对焊缝金属的微观组织、力学性能和强韧化机理进行分析。结果表明,焊缝金属微观组织主要由板条贝氏体、粒状贝氏体、针状铁素体和细晶铁素体组成。贝氏体组织内部的高密度位错相互作用,对于提高焊缝金属强度具有很大的作用。焊缝金属中存在的少量的M-A组元,在铁素体基体上弥散分布并阻碍裂纹扩展,一定程度上提高了焊缝金属的强度和韧性,但其强化作用十分有限。焊缝金属中存在的少量非金属夹杂物,一方面细化晶粒,另一方面促进针状铁素体形核,提高了焊缝金属强度和韧性,少量的非金属夹杂物并不会大幅损害焊缝金属的韧性。焊缝金属的平均屈服强度为793 MPa,伸长率17.2%,-50℃KV2冲击功131 J,焊缝金属的强韧性匹配良好。The 10Ni5CrMoV steel plate is welded with pulsed GMAW process using new high strength and high toughness steel welding wire,and the microstructure,mechanical property,strengthening and toughening mechanism of weld metals are analyzed.The results showed that the microstructure of weld metals are lath bainite,granular bainite,acicular ferrite and fine grain ferrite.The high-density dislocations in bainite improved the strength of weld metals.A small amount of M-A constituent in the weld metal is dispersed on the ferrite matrix and hindered the crack propagation,which improves the strength and toughness of the weld metal to a certain extent,but its strengthening effect is limited.A small amount of nonmetallic inclusion in weld metals could refine grains and promote the formation of acicular ferrite,which could improve the strength and toughness of weld metals and not damage the toughness.The yield strength of weld metals is 793 MPa,the elongation is 17.2%,the KV2 impact energy at-50℃is 132 J,good mechanical property weld metals are obtained.

关 键 词：焊缝金属 强韧性 微观组织 

分 类 号：TG444[金属学及工艺—焊接]