摘要
设计了2种不同碳含量的Fe-Mn-Si系热轧汽车用钢板,考察了传统淬火-回火(Q-T)和新型淬火-分配-回火(Q-P-T)工艺对钢板的显微组织和力学性能的影响。结果表明:在Q-T工艺下增加碳含量会提高钢板的强度但降低塑性,Q-P-T工艺下增加碳含量则会同时提高钢板的强度和塑性,Q-P-T工艺处理的Fe-0.38C-0.02Nb钢板的强塑积达到了33577 MPa·%。经Q-T工艺处理的钢板的显微组织均为板条马氏体+薄膜状残留奥氏体,经Q-P-T工艺处理的钢板的显微组织均为板条马氏体+薄片状残留奥氏体。经Q-P-T工艺处理的Fe-0.38C-0.02Nb钢板中二次裂纹数量较少、板条马氏体更均匀细小、NbC相的数量更多,从而保证了钢板的高强塑性。
Two kinds of hot-rolled Fe-Mn-Si steel plates for automobile with different carbon contents were designed,and the effects of traditional quenching and tempering(Q-T)and new quenching-distribution-tempering(Q-P-T)processes on the microstructure and mechanical properties of the steel plate were investigated.The results showed that(a)the increase in carbon content under the Q-T process would increase the strength but reduce the plasticity of the steel plate,while the increase in carbon content under the Q-P-T process would increase the strength and plasticity of the steel plate simultaneously,the product of strength and elongation of the Fe-0.38C-0.02Nb steel plate treated by Q-P-T process was up to 33577 MPa·%;(b)the microstructure of the steel plate treated by Q-T process was composed of lath martensite and film retained austenite,and the microstructure of the steel plate treated by Q-P-T process was composed of lath martensite and lamellar retained austenite;(c)the Fe-0.38C-0.02Nb steel plate treated by Q-P-T process exhibited less secondary cracks,more uniform and fine lath martensite and more amount of NbC phase,thus ensuring high strength and high plasticity of the steel plate.
作者
程丽群
宋凌鹏
CHENG Liqun;SONG Lingpeng(Nanjing Vocational Insititute of Transport Technology,Nanjing Jiangsu 211188,China;Nanjing University of Aeronautics and Astronautics,Nanjing Jiangsu 210016,China)
出处
《上海金属》
CAS
2021年第4期56-62,共7页
Shanghai Metals
基金
江苏省高校“青蓝工程”资助项目(苏2019-03)
国家级职业教育教师教学创新团队课题(YB2020060104)。
关键词
汽车钢板
碳含量
热处理
显微组织
力学性能
automobile steel plate
carbon content
heat treatment
microstructure
mechanical property
