摩擦堆焊过程中耗材热力过程数值模拟

采用刚粘塑性材料模型,借助有限元软件对摩擦堆焊过程耗材三维温度场与变形场进行了耦合计算,分析了耗材的温度变化及变形情况,讨论了影响温度变化的因素,并用热电偶测量了耗材的温度变化情况.模拟结果显示,耗材摩擦界面处温度的升高先急后缓,待系统进入准稳态,摩擦界面上温度也基本恒定,耗材端部存在一定温度梯度.耗材端部摩擦界面处最先进入热塑性状态并发生变形.模拟结果与试验结果吻合良好,再现了摩擦堆焊过程中耗材的温度变化及变形.模拟结果可为摩擦堆焊机理研究及确定关键工艺参数提供理论指导.

Numerical simulation of consumable-rod’s thermal-mechanical behavior in friction surfacing

By finite element method and rigid-viscoplastic model,the coupling of 3-D temperature field and deformation field of consumable-rod during friction surfacing process was simulated.Temperature change and deformation of consumable-rod were analyzed.The factors influencing temperatures were discussed. Temperature change of consumable-rod was measured by thermocouple.It was showed in the simulation results that the temperature increase rate at friction interface was higher at first,then became lower.Once the friction system became quasi-steady,the temperature here would be stable approximately.Special temperature gradient was found at consumable-rod's bottom end.The friction interface firstly became viscoplastic and then deformed.The largest effective strain existed near the center of the bottom of the circle.The simulation results are consistent with experiments,reappearing temperature change and deformation of consumable-rod during friction surfacing.The results can be helpful in the study of process mechanism and supplying the theoretical guide to choose key technical parameters in engineering practice.