热处理工艺对中碳贝氏体钢组织与性能的影响

Effect of Heat Treatment Process on Microstructure and Properties of Medium Carbon Bainite Steel

热处理工艺对中碳贝氏体钢组织与性能有着重要的影响,本文通过控制中碳贝氏体钢的等温淬火温度和等温淬火时间来研究热处理工艺对中碳贝氏体钢组织与性能的影响。结果表明:随着等温淬火温度的升高,在相同的等温淬火时间内,试验钢的下贝氏体数量增多,下贝氏体组织逐渐变得粗大。随着等温淬火时间的延长,在相同的等温淬火温度内,试验钢的下贝氏体组织数量明显增多,硬度逐渐下降,而冲击韧性明显上升。经过920℃×1.5 h+290℃×3 h热处理后试验钢洛氏硬度可达到49.2HRC,冲击韧性可达167 J/cm^2,可以满足犁铧的工况条件要求。

The heat treatment process has an important influence on the microstructure and properties of medium carbon bainite steel. The influence of heat treatment process on the microstructure and properties of medium carbon bainite steel is studied by controlling the austempering temperature and austempering time of medium carbon bainite steel. The results show that as the austempering temperature increases,the number of lower bainite in the test steel increases and the lower bainite structure becomes coarser in the same austempering time. With the extension of the austempering time,the number of lower bainite structure of the test steel increased significantly,the hardness gradually decreased,and the impact toughness increased significantly in the same austempering temperature. After heat treatment at 920 ℃ ×1.5 h ＋290 ℃ ×3 h,the Rockwell hardness of the test steel can reach 49.2 HRC,and the impact toughness can reach 167 J/cm^2,which can meet the working conditions of the ploughshare.