Q&P工艺对38MnB5Nb超高强钢力学性能与微观组织的影响  

Influence of Q&P process on mechanical properties and microstructure of 38MnB5Nb ultra high strength steel

作　　者：杨杰 王德成 李贤君 巫小林 侯俊卿 杨涛 张赛 Yang Jie;Wang Decheng;Li Xianjun;Wu Xiaolin;Hou Junqing;Yang Tao;Zhang Sai(Beijing Research Institute of Mechanical&Electrical Technology Co.,Ltd.,CAM,Beijing 100083,China;China Academy of Machinery Science and Technology,Beijing 100089,China)

机构地区：[1]中国机械总院集团北京机电研究所有限公司,北京100083 [2]中国机械科学研究总院集团有限公司,北京100089

出　　处：《金属热处理》2024年第2期77-83,共7页Heat Treatment of Metals

基　　金：高强板精密成形控性工艺与装备创新团队;高性能薄钢板在线连续式带张力热处理工艺与装备关键技术(029237106)。

摘　　要：为了提高先进高强钢强塑积,满足汽车轻量化发展要求,以先进高强钢38MnB5Nb为研究对象,讨论其在不同配分温度和配分时间的Q&P工艺下力学性能与微观组织的变化特征,并确定该钢种较优的Q&P工艺参数窗口。结果表明,Ms~Mf之间采用低温长时配分和高温短时配分工艺时,38MnB5Nb钢可以获得较好的强塑性匹配。其中,220℃配分90 s和280℃配分60 s条件下试样强塑积均超过30 GPa·%,分别为35.09 GPa·%和33.23 GPa·%。微观组织方面,相同配分时间随着配分温度的升高板条马氏体逐渐发生粗化现象,相同配分温度随着配分时间的增加马氏体回火现象愈发明显,且伴随碳化物的析出。In order to improve the product of strength and elongation of advanced high⁃strength steel and meet the requirements of automotive lightweight development,advanced high⁃strength 38MnB5Nb steel was taken as the research object,the changes in mechanical properties and microstructure under Q&P processes with different partitioning temperatures and partitioning time were discussed,and the optimal Q&P process parameter window for this steel grade was determined.The results show that between Ms and Mf,using both low⁃temperature long⁃term partitioning and high⁃temperature short⁃term partitioning processes,the 38MnB5Nb steel can achieve good strength and plasticity matching.Among them,under the conditions of 90 s at 220℃and 60 s at 280℃,the product of strength and elongation of the specimens exceeds 30 GPa·%,which are 35.09 GPa·%and 33.23 GPa·%,respectively.In terms of microstructure,the lath martensite coarsens gradually with the increase of partitioning temperature at the same partitioning time,and the tempering phenomenon of martensite becomes more obvious with the increase of partitioning time at the same partitioning temperature,accompanied by carbide precipitation.

关 键 词：38MnB5Nb钢 Q&P 强塑积 力学性能 微观组织 

分 类 号：TG306[金属学及工艺—金属压力加工]