两种变强度热冲压软区模具钢的适用性研究

Study on applicability of two kinds of variable strength hot stamping soft zone die

在B柱变强度热冲压工艺中,其上部需要较高的强度以支撑车顶,其下部需要较高的韧性以吸收侧撞冲击功。当前,主要通过控制热冲压软区模具温度达到变强度要求,经模拟确认应将软区模具保温在500℃以上,以实现B柱变强度热冲压工艺。将新研发的SDCM钢和H55钢作为试验钢,研究两者在500℃和580℃下的抗回火稳定性以及500℃和600℃下的高温摩擦磨损性能。研究表明,两者均可在500℃下长期工作,然而,SDCM钢在580℃下的高温热稳定性能较好,在600℃下的高温摩擦磨损性能较好,因而认为SDCM钢更符合变强度热冲压软区模具钢的使用要求。

In the variable strength hot stamping process of B-pillar,the upper part requires higher strength to support the roof,and the lower part requires higher toughness to absorb side impact energy.At present,it was achieved mainly by controlling the temperature of the variable strength hot stamping soft zone die.It was determined by simulation that the soft zone temperature should be kept above 500℃in order to realize the variable strength hot stamping process of B-pillar.In this paper,the newly developed SDCM and H55 steel were used as test steels to study their temper resistance stability at 500℃and 580℃and their high temperature friction and wear properties at 500℃and 600℃.The results showed that both of them have the ability to work for a long time at 500℃.However,SDCM steel had better thermal stability at 580℃and better high temperature friction and wear properties at 600℃.Therefore,SDCM steel is considered to be more in line with the requirements of variable strength hot stamping soft zone die steel.