超高强钢板热成形模具的热力耦合分析  

Thermal-mechanical Coupling Analysis on Hot Forming Die of Ultra-high-strength Steel Sheet

作　　者：谢晖[1] 何全福 蒋浩民 吴磊 

机构地区：[1]湖南大学汽车车身先进设计制造国家重点实验室,湖南长沙410082 [2]宝钢集团汽车用铜开发与应用技术国家重点实验室,上海201900

出　　处：《热加工工艺》2014年第23期149-153,共5页Hot Working Technology

基　　金：国家科技支撑计划项目(2012BAF12B20);汽车用钢开发与应用技术国家重点实验室开放课题(2012);国家“863”项目(2013AA040605)

摘　　要：根据热成形模具温度与应力的相互关系及变化规律,应用ABAQUS软件对超高强钢板热成形过程进行了热力耦合数值模拟。分析表明:凹、凸模圆角与板料接触最早且接触时间最长,模具圆角处产生热应力集中;模具温度在淬火初期达到最大值,随着淬火的进行,模具温度冷却速度逐渐减小;模具热应力在2.5 s内变为325 MPa,热应力较高的变化频率及过大的变化幅值,极易造成模具热疲劳;模具温度及热应力曲线表明,温差是产生热应力的原因,并随温度变化;无热传递条件下进行模具机械应力分析,测量后得到模具应力、热应力、机械应力比为:11.25∶10.31∶1,热应力比重极大。According to the relationship and variation law of temperature and stress between hot-forming die, the hot forming process of ultra-high-strength steel sheet was numerically simulated in thermal-mechanical coupling by using ABAQUS software. The analysis shows that： punch-matrix fillet first contacts sheet and sustains for a long time, the die fillet produces thermal stress concentration; die temperature reaches a maximum at the beginning of quenching, then the cooling rate of the die temperature decreases with quenching continuation; die thermal stress changes to 325MPa within 2.5s, which varies frequently and changes too much easily cause die thermal fatigue. The curve of die temperature and thermal stress shows that thermal stress is caused by temperature difference and changes with temperature. The mechanical stress of the die was analyzed under the conditions of no heat transfer. After measurement, the ratio of die stress, thermal stress and mechanical stress are 11.25：10.31：1, which the proportion of thermal stress is very large.

关 键 词：热成形 热应力 热力耦合 动平衡分析 

分 类 号：TG306[金属学及工艺—金属压力加工]