Q345FRE高铌耐火钢模拟焊接热影响区高温拉伸性能  

High-temperature tensile properties of HAZ in Q345FRE high Nb fire-resistant steel by simulation

作　　者：崔强 刘攀 孟令明 王红鸿[2] Cui Qiang;Liu Pan;Meng Lingming;Wang Honghong(Nanjing Iron and Steel Group Co.,Ltd.,Nanjing 210035,China;Wuhan University of Science and Technology,Collaborative Innovation Center for Advanced Steels,Wuhan 430081,China)

机构地区：[1]南京钢铁有限公司,南京210035 [2]武汉科技大学,高性能钢铁材料及其应用省部共建协同创新中心,武汉430081

出　　处：《焊接》2021年第6期13-18,33,61,62,共9页Welding & Joining

基　　金：国家自然科学基金资助项目(1971165)。

摘　　要：采用热模拟方法,在Gleeble-3500试验机上进行了Q345FRE耐火钢在单道次不同峰值温度、多道次不同峰值温度、不同t 8/5时间下热影响区的600℃高温拉伸试验,研究了不同状态下热影响区的高温拉伸性能、二次高温拉伸及其变化规律。研究结果表明,在单道次和双道次的焊接热影响区中,模拟峰值温度870℃的不完全重结晶区,其600℃的高温屈服强度和抗拉强度最低;模拟峰值温度1320℃的粗晶区,其600℃高温屈服强度和抗拉强度最高且高于母材的强度;模拟不完全结晶区,焊接热输入(t 8/5时间)对600℃高温屈服强度和抗拉强度的影响无明显规律,且当t 8/5≤80 s时,二次过火的热模拟不完全结晶区的强度没有降低。Tensile tests of HAZ in Q345FRE fire-resistant steel at 600℃ under conditions of different peak temperatures in single pass,different peak temperatures in multiple passes and different t 8/5 times were carried out on Gleeble-3500 tester by thermal simulation method.The high temperature tensile properties,secondary high temperature tensile properties and their variations in the heat affected zone under different conditions were studied.The results showed that in the HAZs of single pass and double pass,the incomplete recrystallization zone at 870℃ peak temperature was simulated and its high temperature yield strength and tensile strength at 600℃were the lowest.The coarse-grained zone at 1320℃peak temperature was simulated and its high temperature yield strength and tensile strength at 600℃ were the highest and higher than those of parent metal.The effect of welding heat input(t 8/5)on high temperature yield strength and tensile strength at 600℃was not obvious the incomplete recrystallization zone at 870℃simulation peak temperature.The strength of the incomplete crystallization zone after secondary overheating by thermal simulation of did not decrease at t 8/5≤80 s.

关 键 词：耐火钢 焊接热影响区 高温拉伸性能 

分 类 号：TG407[金属学及工艺—焊接]