感应预热对激光沉积修复TA15钛合金显微组织和残余应力的影响

利用6 kW光纤激光器的激光沉积修复系统和电磁感应加热设备，采用TA15钛合金粉末在基板未预热和预热到200℃、400℃时分别进行激光沉积修复实验。利用光学显微镜、显微硬度计、压痕法应力测试仪对激光沉积修复试样的显微组织、显微硬度、残余应力进行测试分析，得到不同预热温度对激光沉积修复显微组织、显微硬度、残余应力的影响规律。结果表明:随着感应预热温度的升高，片层组织变得粗大，初生相生长更加充分；组织分布均匀化，显微硬度轻微降低；残余应力明显减小。为感应加热辅助激光沉积修复提供指导依据。

Effects of induction preheating on microstructure and residual stress of laser deposition repair TA15 titanium alloy

Both 6 kW fiber laser deposition repair system and electromagnetic induction heating equipment were utilized, laser deposition repair experiments were respectively done by TA15 titanium powder under substrate without preheating and preheating at 200℃ and 400℃. Then microstructure, microhardness and residual stress were tested and analyzed through optical microscope, microhardness tester and indentation stress tester, the influence of microstructure, microhardness and residual stress in different substrate preheating temperature on the laser deposition repair sample was achieved. Results show that microstructure of lamella becomes thicker and primary grow more fully; microhardness of material is slightly reduced; residual stress is effectively reduced with the increasing of preheating temperature. The guidance basis for laser deposition repair assisted by induction heating is provided.