高强钢热成形模具局部脱空冷却行为  

Cooling behavior of local hollowed die in hot stamping of high strength steel

作　　者：黄旭 胡开广 郭子峰 郑学斌 牛涛 李学涛 HUANG Xu;HU Kai-guang;GUO Zi-feng;ZHENG Xue-bin;NIU Tao;LI Xue-tao(Research Institute of Technology,Shougang Group Co.,Ltd.,Beijing 100043,China)

机构地区：[1]首钢集团有限公司技术研究院,北京100043

出　　处：《塑性工程学报》2023年第10期60-70,共11页Journal of Plasticity Engineering

摘　　要：采用有限元与实验相结合的方法,对热冲压分区冷却保压淬火过程中的温降行为进行了研究,采用仿真软件建立了局部脱空模具热冲压有限元模型,开展了不同参数下局部软化区域的温降行为研究,通过局部脱空模具保压淬火实验,验证了通过局部脱空模具实现零件局部软化的可行性。结果表明,局部脱空模具保压淬火过程中,脱空位置处板料温降主要靠与相邻区域的热传导实现,模具孔径和模具温度对脱空位置板料温降影响较大,板料-模具接触换热系数和间隙换热系数对脱空位置板料温降影响较小,通过控制模具脱空孔径和保压淬火时间可以有效抑制马氏体相变,进而实现零件局部软化。The temperature drop behaviors in the process of zonal cooling and pressure holding quenching of hot stamping were studied by combining finite element and experiments methods.The finite element model of local hollowed die in hot stamping was established by simulation software,and the temperature drop behaviors of local softening region with different parameters were studied.The feasibility of local softening of parts by local hollowed die was verified by the pressure holding quenching experiments of local hollowed die.The results show that in the process of pressure holding quenching of local hollowed die,the temperature drop of sheet metal at the hollowed position is mainly realized by heat conduction with the adjacent areas.The die aperture diameter and die temperature have great influence on temperature drop of sheet metal at the hollowed position,and the sheet metal-die contact heat transfer coefficient and gap heat transfer coefficient have little influence on temperature drop of sheet metals at the hollowed position.The martensitic phase transformation can be effectively inhibited by controlling the die aperture diameter and the pressure holding quenching time,and then the local softening of parts can be realized.

关 键 词：高强钢 热成形 模具局部脱空 冷却行为 局部软化 

分 类 号：TG306[金属学及工艺—金属压力加工]