用于冷冲模的高速钢热处理工艺参数

摘要

为了改进用于冷冲模的高速钢W18Cr4V热处理工艺参数,研究淬火温度、回火温度、回火次数以及残余奥氏体含量对材料表面硬度和粗糙度的影响.结果表明:W18Cr4V中的残余奥氏体含量随淬火温度和回火温度的变化而变化.残余奥氏体含量与材料硬度之间呈开口向下的二次曲线关系.当W18Cr4V中残余奥氏体含量为30％～55％时,其硬度高、磨削性好、表面粗糙度低.当W18Cr4V先在1150C淬火,然后分别在300 ～400C和570C下回火时,可得到稳定的马氏体组织,且其表面硬度最高、表面粗糙度最低.采用该工艺参数制造冷冲模,热处理时间减少40％,节约电能35％以上.%To improve the heat processing parameters in cold-punching mold manufacturing with highspeed steel W18Cr4V, the quenching temperature, tempering temperature, tempering times and influence of the volume of retained austenite on surface hardness and roughness of the material are researched. The results indicate that the volume of retained austenite in W18Cr4V changes with the change of quenching temperature and tempering temperature. The relation between the surface hardness and the volume of retained austenite can be illustrated with a downward open quadratic curve. When the volume of retained austenite in W18Cr4V amounts to 30% -55% , it is of higher surface hardness, better grindability, and lower surface roughness. Stable martensite structure, maximum surface hardness and minimum surface roughness can be obtained when W18Cr4V is quenched at 1 150 ℃ firstly and then tempered at 300 ~ 400℃ and 570℃ respectively. Adoption of these processing parameters in manufacturing cold-punching molds can reduce the heat processing time by 40% and save energy consumption by more than 35%.