摘要
结合作者的近期研究结果以及业界同行的研究,从乘用车和商用车应用两个角度,对1500~2000 MPa铌微合金化的热成形钢开发及性能研究进展进行了总结分析,发现当Nb含量(质量分数)>0.03%时,钢材晶粒细化显著,晶粒尺寸可以达到传统热成形钢晶粒尺寸的1/3~2/3,甚至更小;在传统的热成形钢中添加Nb或者复合添加后,纳米析出相尺度主要为1~30 nm,而且平均尺度在10 nm左右。铌微合金化通过抑制了氢脆的4个触发条件,进而有效降低热成形钢及零部件的氢脆风险。铌微合金化使热成形钢的尖角冷弯角度提高了10%~15%,可以使零件断裂指数提高45%~80%,铌微合金化热成形钢在应力三轴度(-0.6~0.4)状态下临界断裂应变更高,提高热冲压成形零件的抗碰撞断裂能力。铌微合金化热成形钢在乘用车和商用车上的应用可以有效减低减轻质量,实现轻量化,并提高安全性能。
Combined with the author’s and other scholars’recent research results,this paper summarizes and analyzes the development and performance research progress of 1500~2000 MPa Nb microalloying hot-formed steel,from the application of passenger cars and commercial vehicles.It is found that when the Nb content(mass fraction)is>0.03%,the grain of the steels is significantly refined,and the grain size can reach 1/3~2/3,or even smaller than that of the traditional hot-formed steels.The size of nano precipitates is mainly 1~30 nm,and the average size is about10 nm,when Nb is added to the traditional hot-formed steel.Nb microalloying can effectively reduce the hydrogen embrittlement risk of hot-formed components,by inhibiting the 4 triggering conditions of hydrogen embrittlement.Nb microalloying can increase the cold bending angle of hot-formed steel by 10%~15%,and the fracture index of steel parts by 45%-80%.The critical fracture stress of Nb-bearing hot-formed steel increases at stress triaxiality(-0.6~0.4),which improves the anti-collision fracture capability of hot-stamped components.The application of Nb-bearing hotformed steel in passenger cars and commercial vehicles can effectively reduce the weight and improve safety.
作者
路洪洲
赵岩
冯毅
马鸣图
郭爱民
Lu Hongzhou;Zhao Yan;Feng Yi;Ma Mingtu;Guo Aimin(CITIC Metal Co.,Ltd,Beijing 100004;Beijing Institute of Technology Chongqing Innovation Center,Chongqing 401122;China Automotive Engineering Research Institute Co.,Ltd,Chongqing 401122)
出处
《汽车工艺与材料》
2021年第4期23-32,共10页
Automobile Technology & Material
基金
汽车用超高强度钢热冲压成形组织强韧性机理与调控(U1564203)
高强度钢的氢致延迟断裂行为表征研究(LP180100431)。
关键词
安全
氢脆
韧性
弯曲角
断裂卡片
轻量化
Safety
Hydrogen embrittlement
Toughness
Bending angle
Fracture card
Lightweight
作者简介
路洪洲(1981-),男,教授级高级工程师,博士学位,研究方向为汽车制造。
