论文部分内容阅读
采用箱式电阻炉对铸态高Cr冷作模具钢进行了不同温度的高温处理,并对热处理试样显微组织进行了观察,对拉伸、硬度等力学性能进行了检测。结果表明,随着处理温度的升高,试验钢球化退火后组织中碳化物颗粒先逐渐粗化,1170℃后又明显细化,网状共晶渗碳体含量逐渐减少,1170℃时其含量降低至8%左右,基本消除对基体割裂的影响;回火组织主要由回火马氏体和未溶碳化物组成,1150℃以上处理的试验钢回火组织中还出现少量残余奥氏体;随处理温度的提高,试验钢伸长率先升高,1150℃处理时伸长率有所下降,1170℃处理时升高达到最大值,抗拉强度和硬度的变化趋势基本一致,均是先逐渐下降,至1170℃处理时又有所升高。
The box-type resistance furnace was used to treat the as-cast high Cr cold work die steel under high temperature. The microstructure of the heat-treated sample was observed. The tensile and hardness mechanical properties were tested. The results showed that with the increase of the treatment temperature, the carbide particles in the microstructure of the test steel gradually roughened and refined at 1170 ℃, and the reticular eutectoid cementite content gradually decreased. At 1170 ℃ The content is reduced to about 8%, basically eliminating the impact on the matrix fracture; tempering microstructure mainly composed of tempered martensite and undissolved carbide, tempered steel specimens treated at 1150 ℃ or above a small amount of retained austenite ; With the increase of the treatment temperature, the elongation of the test steel first increased, the elongation at 1150 ℃ treatment decreased, the maximum reached at 1170 ℃, the tensile strength and hardness trends are basically the same, are the first Gradually decreased to 1170 ℃ treatment has increased.