高性能桥梁钢模拟焊接热影响区组织与性能研究  

Study on Microstructure and Mechanical Properties of HAZ in High Performance Bridge Steel for Welding Simulation

作　　者：王强 王云阁 尹绍江 

机构地区：[1]河钢唐钢技术中心

出　　处：《宽厚板》2018年第1期10-12,共3页Wide and Heavy Plate

摘　　要：采用热模拟试验机Gleeble 3 800对高性能桥梁钢Q420q D焊接热影响区组织及韧性进行分析,主要研究峰值温度(Tmax)、冷却时间(t8/5)对焊接过程热影响区组织长大及低温韧性的影响。结果表明:Tmax为1 000℃时,模拟焊接热影响区组织为细小的铁素体+少量珠光体,韧性最好;Tmax为1 200~1 300℃时,组织为粗大的上贝氏体及粒状贝氏体,韧性最差;Tmax为1 400℃时,随着冷却时间(t8/5)的延长,粗晶区组织明显长大,先共析铁素体数量增加,M-A组元尺寸变大,韧性降低。The article describes the analysis on microstructure and toughness in simulated welding HAZ of high performance bridge steel Q420qD by Gleeble 3 800 thermal simulator, which is to mainly study the effects of peak tem-perature Tmax and cooling time t8/5 on microstructure growth and low temperature toughness of HAZ during welding. The results show that the microstructure of simulated welding HAZ consists of fine ferrite and less pearlite with highest toughness when Tmax is 1 000℃ ,but coarse upper bainite and granular bainite with lowest toughness when Tmax is be-tween 1 200 and 1 300 ℃ , while the microstructure at coarse grain zone grows up, the volume fraction of proeutectoid ferrite and the size of M - A constituent increase, the toughness deteriorates as the cooling time t8/5 extends when Tmax is 1 400 T.

关 键 词：桥梁钢 热影响区 焊接热模拟 热输人量 

分 类 号：TG457.11[金属学及工艺—焊接]