论文部分内容阅读
研究了回火温度对Si-Mn系中碳弹簧钢组织及性能的影响。对实验室试制的Si-Mn系中碳弹簧钢进行900℃淬火,300~550℃回火实验,分析了不同回火温度对实验钢硬度以及显微组织的影响。结果表明:实验钢在350℃以下回火,组织为回火马氏体;400~450℃回火,组织为回火屈氏体;500℃以上回火,组织为回火索氏体。实验钢硬度随回火温度的升高而下降,在400℃以下的低温回火区间下降较慢,在400℃以上回火时下降较快。在500℃回火时实验钢显现抗回火软化效应,硬度下降趋势减缓。
The effect of tempering temperature on microstructure and properties of Si-Mn middle carbon spring steel was studied. The Si-Mn medium carbon spring steel trial-produced in laboratory was subjected to tempering at 900 ℃ and tempering at 300-550 ℃. The effects of different tempering temperature on the hardness and microstructure of the test steel were analyzed. The results show that the experimental steel is tempered at 350 ℃, the microstructure is tempered martensite, tempered at 400-450 ℃, tempered troostite is formed, and the tempered sorbite is tempered above 500 ℃. The hardness of experimental steel decreased with the increase of tempering temperature, but decreased slowly in the low temperature tempering range below 400 ℃, and decreased rapidly when tempering above 400 ℃. When tempering at 500 ℃, the experimental steel shows a tempering-softening effect and the hardness decreases slowly.