Numerical simulation of temperature field in multilayer laser cladding

激光熔覆多层涂层温度场的数值模拟 Numerical simulation of temperature field in multilayer laser cladding 孙越 SUN Yue 1 first-author 张兆林 ZHANG Zhaolin 1 刘欣 LIU Xin 1 牛安平 YANG Jian 2 杨坚 LU Maoqi 1 卢茂奇 Datang Northeast Electric Power Test & Research Institute 2 韩立梅 North China Electric Power University 2 大唐东北电力试验研究院有限公司 大唐东北电力试验研究院有限公司 大唐国际沈东热电有限责任公司  3. 华北电力大学  4. 长春金融高等专科学校  大唐国际沈东热电有限责任公司  3. 华北电力大学  4. 长春金融高等专科学校  基于ANSYS生死单元技术,建立了多层激光熔覆三维有限元分析模型,获得多层激光熔覆温度场的分布规律,同时分析预热温度对激光熔覆热循环的影响。试验结果表明,平行于热源移动方向的节点加热速度较快,降温速度缓慢;垂直于热源移动方向的节点,距离熔覆层中心越近,加热速度和冷却速度越大。y方向的结合处节点的温度梯度大于x方向的结合处节点的温度梯度;热输入保持不变时,随着预热温度的升高,加热速度变化较小,峰值温度升高,相变温度以上停留时间变长,但高温停留时间变化不大。预热温度为200 ℃时,t8/5约为未预热下的3.2倍,预热可以减小熔覆层开裂倾向,有效降低涂层应力。 Based on the ANSYS "element birth and death technology",a three-dimensional finite element analysis model of multilayer laser cladding is established. The distribution law of temperature field of multilayer laser cladding is obtained,and the influence of preheating temperature on thermal cycle of laser cladding is analyzed. The experimental results show that the heating speed of the nodes parallel to the moving direction of the heat source is faster and the cooling speed is slower. For the nodes perpendicular to the moving direction of the heat source,the closer to the center of the cladding layer,the faster the heating speed and cooling speed.The temperature gradient of node in Y direction is greater than that in X direction. When the heat input remains constant,as the preheating temperature increases,the heating speed changes little,the peak temperature increases,and the residence time above the phase transition temperature stays longer,but the residence time at high temperature has little change. When the preheating temperature is 200 ℃,the t8/5 parameter is about 3.2 times of that without preheating,and the cracking tendency of the cladding can be reduced by preheating. The simulation results show that preheating can effectively reduce the coating stress. 激光熔覆 温度场 ANSYS生死单元 预热 残余应力 laser cladding temperature field ANSYS element birth and death preheating TG665;TG174.4 2022-03-08 5 51