高强度耐候钢焊接热影响区的组织与韧性  

Microstructure and Toughness of Welding Heat Affected Zone of High Strength Anti-weathering Steel

作　　者：王艳杰[1] 刘建宇[1] 张景泽[1] 王虎[1] 张程[1] 

机构地区：[1]北华航天工业学院材料工程学院,河北廊坊065000

出　　处：《北华航天工业学院学报》2016年第4期4-7,共4页Journal of North China Institute of Aerospace Engineering

基　　金：廊坊市科技局项目(2013011014);河北省大学生创新创业训练计划项目(201511629016)

摘　　要：通过热模拟实验研究在不同的焊接冷却速度下,两种不同强度级别的09Cu PTiRE耐候钢焊接热影响区的组织和韧性变化;结果表明随着焊后冷却速度减慢,两种级别的09Cu PTiRE耐候钢热影响区组织开始粗化,且贝氏体的含量逐渐减少,铁素体的含量逐渐增加,在相同的冷速下360MPa级09Cu PTiRE耐候钢的组织粗化度比490MPa级09Cu PTiRE耐候钢严重;随着冷却速度减慢,两种级别耐候钢热影响区的冲击韧性由高到低的变化,360MPa级09Cu PTiRE耐候钢热影响区由韧窝断裂转变为准解理断裂;490MPa级09Cu PTiRE耐候钢由韧窝断裂转变为准解理和解理断裂方式。当焊接冷速t8/5≥18s,490MPa级09Cu PTiRE耐候钢热影响区韧性较低,影响因素为热影响区组织的粗化、硫化物夹杂及夹杂物形状不规则等。Under different welding cooling rates, the microstructure and toughness of welding heat affected zone of 09CuPTiRE weathering steel with two different strength grades are studied by thermal simulation experiment. The results show that the microstructure of the heat affected zone of 09CuPTiRE weathering steel gradually becomes coarse with the increase of the cooling time, and the content of bainite decreases, and the content of ferrite increases gradually. At the same cooling rate, the microstructure of 360M Pa grade weathering steel is coarser than that of 490MPa grade 09CuPTiRE weathering steel. With cooling rate slowing down, the impact toughness of heat affected zone of two grades weathering steel changes from high to low. The fraetography of 360MPa grade 09CuPTiRE weathering steel changes from dimple fracture to quasi-cleavage fracture, and 490MPa grade weathering steel changes from dimple fracture to quasi-cleavage and cleavage fracture. When the welding cooling time t 8/5 is longer than 18s, heat af- fected zone toughness of 490MPa grade weathering steel is lower. The influence factors are the coarsening of the microstructure in heat affected zone, sulfide inclusion and inclusion shape irregular etc.

关 键 词：09CuPTiRE 热影响区 组织 韧性 

分 类 号：TG406[金属学及工艺—焊接]