基于温度-组织-应力三场耦合的耐磨钢淬火工艺

Quenching process of wear resistant steel TNM360 with temperature-microstructure-stress coupling

通过实验测定了TNM360耐磨钢在20~900℃范围内的比热容和热导率;测定了耐磨钢的等温转变曲线(TTT曲线)以及100~1000℃之间每隔100℃的真应力真应变曲线以及马氏体相变膨胀曲线,计算得出马氏体转变相关系数;针对10 mm厚耐磨钢板,设计3种淬火冷却工艺:第一与第二冷却工艺相比,钢板运行速度相同,冷却器开启组合不同;第一与第三冷却工艺相比,冷却器开启组合相同,而钢板运行速度不同。并利用Ansys和Matlab对冷却过程的温度场、组织场以及应力场进行模拟计算。结果表明:TNM360耐磨钢3种工艺终冷温度均在技术要求范围内,终冷后组织均为马氏体及少量残留奥氏体,但在冷却器全开,钢板运行速度为1.6 m/s,淬火后残余应力及应变最小,板形最好。

The specific heat capacity and thermal conductivity of TNM360 wear-resistant steel were tested in the temperature range from20 ℃ to 900 ℃. TTT( Time,Temperature,Transformation) curve and the martensite transformation curve of the TNM360 steel were obtained by experiment. And the true stress-strain curves were tested every 100 ℃ from 100 ℃ to 1000 ℃. By Ansys and Matlab software's,the temperature,microstructure and stress fields of TNM360 steel plate with 10 mm thickness were calculated under three cooling processes. The running velocity of the first and the second cooling process was the same,but the cooler combination was different;the cooler combination of the first and the third cooling process was the same,but the running velocity was different. The results show that the temperatures after cooling can meet the technical requirements under three cooling processes,and the microstructure consists of martensite and a small amount of residual austenite. When the coolers are all open and the running velocity of the steel plate is 1. 6 m / s,the residual stress and strain after quenching are minimum.