摘要
使用不同线速度对Ф13.6 mm的55SiCr弹簧钢线材进行了在线快速感应加热热处理。采用光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)、电子背散射衍射(EBSD)及拉伸实验等分析了55SiCr弹簧钢热处理后的微观组织和力学性能。结果表明:在线快速感应加热热处理可细化实验钢的奥氏体晶粒尺寸,不同线速度下实验钢的微观组织主要由残留奥氏体和回火屈氏体构成并含有较高密度的位错结构。随着线速度的降低,相应回火保温时间的延长,实验钢的原奥氏体晶粒尺寸无明显变化,残留奥氏体相含量逐渐减少,α相含量逐渐增加,小角度晶界所占比例随回火时间的延长而逐渐减小。随着线速度的降低,实验钢在快速回火阶段的回复软化作用占据了主导作用,位错密度显著降低,导致其强度逐渐降低,断面收缩率增大。
55 SiCr spring steel wire with diameter of 13.6 mm was treated by online rapid induction heating at different wire speeds.Microstructure and mechanical properties of the 55 SiCr spring steel were analyzed by means of optical microscope(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),electron backscattered diffraction(EBSD)technique and tensile test.The results show that the austenite grain size of the experimental steel can be refined by online rapid induction heat treatment.The microstructure of the experimental steel at different wire speeds is mainly composed of retained austenite and tempered troostite,and contains high-density dislocation structure.With the decrease of wire speed and the increase of tempering holding time,the primary austenite grain size of the experimental steel has no obvious change,the retained austenite phase content gradually decreases,theαphase content gradually increases,and the proportion of small angle grain boundary gradually decreases with the increase of tempering time.With the decrease of wire speed,the recovery softening of the experimental steel plays a leading role in the rapid tempering stage,and the dislocation density decreases significantly,resulting in the gradual decrease of its strength and the increase of reduction of area.
作者
戴启雷
金雷
任英志
杨天宝
陈雯
李坤
DAI Qi-lei;JIN Lei;REN Ying-zhi;YANG Tian-bao;CHEN Wen;LI Kun(College of Mechanical and Vehicle Engineering,Chongqing University,Chongqing 400044,China;Hwaway Technology Co Ltd,Zhuji 311800,China;Chongqing Key Laboratory of Metal Additive Manufacturing(3D Printing),Chongqing 400044,China;State Key Laboratory of Mechanical Transmission,Chongqing 400044,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2022年第8期110-116,共7页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(51975073)
中央高校基本科研业务费(2021CDJQY-024)。
关键词
弹簧钢
在线感应加热
微观组织
力学性能
spring steel
online induction heating
microstructure
mechanical property
