非等温碳分配条件下的热轧DQ&P工艺研究  

Research on hot-rolling DQ&P process under non-isothermal carbon partition

作　　者：李云杰[1] 刘洺甫 胡虹玲 杨靖妍 刘明瑞[1] 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110819

出　　处：《轧钢》2015年第2期13-17,共5页Steel Rolling

摘　　要：为满足汽车轻量化的发展要求,先进高强度钢已成为研究热点,近年来以淬火-分配(Q&P)理念为基础的工艺研究备受关注。本文将Q&P理念引入热轧工艺过程中,并进行了实验研究,即采用直接淬火(DQ)工艺结合非等温条件下碳分配处理(碳分配过程在模拟卷取过程中进行)。实验结果表明:实验钢组织由马氏体、残余奥氏体及少量铁素体组成。当卷取温度为350℃时,实验钢组织中残余奥氏体体积分数较高,达到11.5%,同时抗拉强度达到1 370 MPa,伸长率为14.20%,强塑积为19.5 GPa·%。进行TEM观察,发现马氏体板条束之间存在以薄膜状形态分布的残余奥氏体。In order to satisfy the requirements of lightweight in the automotive industry, advanced high strength steel has become a hot topic. In recent years, the research based on Q＆P concept has been paid extensive atten- tions. The present work takes Q＆P concept into considerations during hot rolling process, combining direct quenching with non-isothermal carbon partition that the partition process will occur during the coiling process. The test results show that martensite, retained austenite and a little ferrite are obtained in the tested steel. When the coiling temperature is at 350℃, the microstructure includes a higher fraction of retained austenite reaching 11.5%,and the tested steel exhibits high ultimate tensile strength exceeding 1 375 MPa and fine elongation of 14.2% and TS ×TEL of 19.5 GPa · % .In addition, there is thin film retained austenite presenting in martensite lath when observed by TEM.

关 键 词：先进高强度钢 直接淬火 非等温碳分配 残余奥氏体 强塑积 

分 类 号：TG161[金属学及工艺—热处理] TG335.11[金属学及工艺—金属学]