回火温度对Q690D级高强结构钢组织和性能的影响  

Effect of Tempering Temperature on Microstructure and Properties of Q690D High-strength Structural Steel

作　　者：李德刚[1,2] 杨维宇[2] 白雅琼[2] 李智丽[2] 王国栋[1] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110004 [2]内蒙古包钢钢联股份有限公司技术中心,内蒙古包头014010

出　　处：《热加工工艺》2014年第8期220-222,225,共4页Hot Working Technology

摘　　要：研究了回火温度对经一定温度淬火后Q690D级高强结构钢组织和力学性能的影响。结果表明：930℃淬火并于350-660℃回火时，随回火温度的升高，Q690D的淬火组织逐渐转变为回火马氏体、回火托氏体和回火索氏体；强度逐渐降低，屈强比逐渐升高，出现了第一、二类回火脆性，当回火温度为640℃时强韧性配合最好，此时Rpo．2=748MPa，Rm=802MPa，A50=41．0％，AKV（20℃）=181J，AKV2（-40C）=97J。The effects of tempering temperature on microstructure and mechanical properties of Q690D high-strength structural steel quenched from a fixed temperature were investigated. The results show that with respect to Q690D steel quenched from 930 ℃, the as-quenched martensite will gradually transform into tempered martensite, tempered troosite and tempered sorbite. Strength gradually decreases, and yield ratio gradually increases. There have been the first and second temper brittleness with the increase of tempering temperature in the range of 350 ℃ to 660℃. The best strength and toughness are achieved when the tempering temperature is 640℃, mechanical properties are as follows： Rp02=748 MPa, Rm= 802 MPa, A 50=41.0%, A kv2 （-20-c）= 181 J,A kv2 （-40℃）=97 J.

关 键 词：Q690D 回火温度 显微组织 力学性能 

分 类 号：TG156.4[金属学及工艺—热处理]