新型模具制取变强度制件及其力学性能研究  

Producing hot stamping parts with variable strengths by a new die and study on mechanical properties of stamping parts

作　　者：包丽[1] 谷泉[2] 蔡有杰[1] 吴志东[1] 刘萌[1] 刘尚[1] 

机构地区：[1]齐齐哈尔大学机电工程学院,黑龙江齐齐哈尔161006 [2]辽宁科技学院机械工程学院,辽宁本溪117004

出　　处：《锻压技术》2017年第9期123-128,134,共7页Forging & Stamping Technology

基　　金：黑龙江省教育厅基本业务专项理工青年骨干项目(135109310)

摘　　要：设计出利用感应加热方式形成变强度制件的热冲压新型分区模具,进行了热-流-固耦合场的理论分析,建立了热-力耦合有限元模型,得到了板料在热冲压过程中温度和维氏硬度的分布。仿真结果表明,当模具感应加热端温度升至400℃时,加热端的冷却速度为13.6℃·s^(-1),冷却速度决定了板料不同温区的微观组织和维氏硬度。利用该模具进行了热冲压实验,对不同温区的微观组织和维氏硬度进行检测。结果表明:该模具可冲压不同高温区(低强度)形状的制件。制件高温区已经基本转化为贝氏体组织,过渡区转化为马氏体、贝氏体和铁素体多相混合组织,低温区转化为板条状马氏体组织。设计出的新型分区模具可以获得变强度制件,为成形复杂变强度零件和工艺参数的优化提供了依据。A new type of hot stamping partition die was designed to form parts with variable strengths by induction heating, and the ther- mal fluid solid coupling theory analysis was carried out. Then, the finite element model with thermal mechanical coupling was established, and the temperature and Vickers hardness distributions of sheet metal in hot stamping were obtained. The simulation results show that the cooling rate cff heating die is 13.6 ℃ ·s^-l when the temperature of induction heating end of the die raises to 400℃, so the microstructure and Vicke~ hardness of sheet metal at different temperatures are determined by different cooling rates. Furthermore, the hot stamping ex- periments are carried out by the die, and the microstructure and Vickers hardness at different temperatures regions are examined. The re- suits show that the new die can form parts with high temperature zone （ low strength）, and the bainite microstructure of stamping parts is transformed from the high temperature zone, the martensite as well as bainite and ferrite muhiphase mixed microstructures are transformed from the transition zone respectively, the lath - shape martensite is transformed from low temperature region. The new hot stamping die can obtain stamping parts with variable strengths and provides the basis for obtaining stamping parts with variable strength and the optimization of process parameters.

关 键 词：新型模具 热冲压 变强度制件 力学性能 有限元模拟 

分 类 号：TG305[金属学及工艺—金属压力加工]