一种汽车用微合金非调质钢的连续冷却转变  

Continuous cooling transformation of a microalloyed non-quenched andtempered steel for automobile

作　　者：赵楠 孙晓冉 王程明 郭维超 赵剑磊 ZHAO Nan;SUN Xiaoran;WANG Chengming;GUO Weichao;ZHAO Jianlei(HBIS Materials Institute,Shijiazhuang 050000,China;Beijing Zhongyongcheng Construction Engineering Inspection Co.,Ltd.,Beijing 101118,China)

机构地区：[1]河钢材料技术研究院,石家庄050000 [2]北京中永成建筑工程检验有限责任公司,北京101118

出　　处：《理化检验（物理分册）》2024年第4期1-4,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

基　　金：河北省自然科学基金钢铁联合基金(E2022318003)。

摘　　要：测定了一种汽车用微合金非调质钢的过冷奥氏体连续冷却转变曲线,研究了冷却速率对相变组织及显微硬度的影响。结果表明:试验钢的临界点A c3为838℃,A c1为732℃;当冷却速率小于0.2℃/s时,试验钢的连续冷却转变产物为铁素体、珠光体和贝氏体;当冷却速率为0.2℃/s时,转变产物中出现马氏体;当冷却速率为5℃/s时,铁素体、珠光体消失,转变产物为贝氏体和马氏体;随着冷却速率的增大,马氏体含量逐渐增多,贝氏体含量逐渐减少,甚至完全消失;当冷却速率增大至20℃/s时,转变产物均为马氏体;随着冷却速率的增大,试验钢的显微硬度呈先快速增长,后增长速率变缓的趋势。The continuous cooling transformation curve of supercooled austenite of a microalloyed non-quenched and tempered steel for automobile was measured,and the effect of cooling rate on phase transformation structure and microhardness was studied.The results show that the critical point A c3 of the test steel was 838℃,and A c1 was 732℃.When the cooling rate was less than 0.2℃/s,the continuous cooling transformation products of the test steel were ferrite,pearlite and bainite.When the cooling rate was 0.2℃/s,martensite appeared in the transformation product.When the cooling rate was 5℃/s,ferrite and pearlite disappeared,and the transformation products were bainite and martensite.With the increase of cooling rate,the content of martensite increased gradually,and the content of bainite decreased gradually or even disappeared completely.When the cooling rate increased to 20℃/s,the transformation products were martensite.With the increase of cooling rate,the microhardness of the test steel increased rapidly at first,and then the growth rate slowed down.

关 键 词：微合金非调质钢 连续冷却转变曲线 临界点 显微组织 显微硬度 

分 类 号：TG151.2[金属学及工艺—热处理] TB31[金属学及工艺—金属学]