45钢激光淬火表面非稳态传热计算方法  

Computational method for unsteady heat transfer on surface of 45 steel during laser quenching

作　　者：张文 郭雨潼 张灵聪 沈锐 石绘[1] 包汉伟 李刚炎[1] Zhang Wen;Guo Yutong;Zhang Lingcong;Shen Rui;Shi Hui;Bao Hanwei;Li Gangyan(School of Automotive Engineering,Wuhan University of Technology,Wuhan Hubei 430070,China)

机构地区：[1]武汉理工大学机电工程学院,湖北武汉430070

出　　处：《金属热处理》2024年第8期232-241,共10页Heat Treatment of Metals

摘　　要：通过显式的二维有限差分方程求解得出45钢激光淬火过程中非稳态传热的温度分布,分析激光功率对单道激光淬火表面温度的影响。利用JMatPro计算得出材料升温和冷却过程的相转变曲线、热物性参数随温度的变化曲线,以及相变临界温度。综合考虑激光热源与相变潜热,建立45钢激光淬火表面非稳态传热模型,对固定热源和移动热源条件的激光淬火进行传热分析。结果表明,固定热源条件下最高温度计算结果误差在7%以内;当激光照射时间为0.5 s、功率介于1300~2600 W时,试件表面温度可被有效控制在720℃到液相线1495℃之间,确保激光淬火过程中固态相变的发生;模型应用于高功率下的单道移动热源激光淬火,可以较好地反映实际的温度变化趋势。Temperature distribution of unsteady heat transfer during laser quenching of 45 steel was obtained by solving an explicit two⁃dimensional finite difference equation,and the effect of laser power on the surface temperature after single pass laser quenching was analyzed.Utilizing JMatPro,comprehensive phase transformation curves,as well as temperature⁃dependent thermophysical properties and phase transformation critical temperatures during heating and cooling processes of the material,were derived.Incorporating both the laser heat source and latent heat of phase transformation,a unsteady heat transfer model for the surface laser quenching of 45 steel was established.This model was then employed to conduct heat transfer analysis under both fixed and moving heat source conditions during laser quenching.The results show that the error of the maximum temperature calculation under fixed heat source condition is within 7%.When the laser irradiation time is 0.5 s and the power is between 1300 W and 2600 W,the surface temperature of the specimen can be effectively controlled between 720℃and liquidus 1495℃,ensuring the occurrence of solid phase transformation during laser quenching process.The model is applied to single pass moving heat source laser quenching at high power,which can better reflect the actual temperature change trend.

关 键 词：激光淬火 非稳态传热 激光热源 相变潜热 相变临界温度 

分 类 号：TG161[金属学及工艺—热处理]