摘要
通过拉伸、弯曲、冲击、硬度试验以及金相分析等对BWELDY700QL4低合金高强钢焊接接头的显微组织和力学性能进行了研究.结果表明:采用YM80-A焊丝焊接BWELDY700QL4低合金高强钢可以获得拉伸、弯曲和冲击性能均良好的焊接接头;其焊缝组织晶界为先共析铁素体、平行排列的无碳贝氏体从晶界伸向晶内,晶内为针状铁素体与珠光体,个别部位有粒状贝氏体.熔合区及粗晶区组织为板条马氏体和少量M-A组元.正火区组织为粒状贝氏体和少量铁素体.BWELDY700QL4焊接接头的硬度值在264～380 HV之间,焊缝处硬度最高,比母材高48～76 HV,热影响区虽有软化现象,但不明显.
Microstructure and properties of BWELDY700QIA welding joint were investigated by tensile,ben- ding,impact and hardness tests and metallographic analysis. The results show that tensile, bending and impact properties of the BWELDY700QIA welding joint welded with YMS0-A welding wire are excellent. The micro- structure in the weld metal contains vast proeutectoid ferrites that locate at grain boundaries, and carbon-free bainites in parallel arrangement which stretch from grain boundary into the grains, which present acicular fer- rites and pearlites. Some granular bainites distribute at exceptional locations. The microstructure in the fusion zone of welds contains lath martensite and martensite-austensite group, and the normalized zone of the welds contains granular bainite and a little amount of ferrite. The hardness of the BWELDY700QIA wels is between 264 and 380 HV,which is 48 -76 HV higher than parent metal.
出处
《大连交通大学学报》
CAS
2012年第3期41-44,共4页
Journal of Dalian Jiaotong University
