Research Of Temperature Fieldand Stree Field Of Laser Deposition Repairing Of Titanium Alloy

Laser Deposition Repairing Technology is an advanced Additive Manufacturing Te chnology which is based on Laser Rapid Forming Technology and Laser Surface Clad ding Technology. Any complex shape damaged and manufacture shortcoming parts can be repaired by using the technology.But there exists complex thermodynamic change in the process, it is hard to make an experimental study on the process, and there e xsits deformation and cracking problem after repairing, a high level of residual stress exsits in the parts, all these produces a serious effect on the quality. If there exists cr acking in the repairing area, non-conforming repaired products produces, the repaired p rocess will be forcefully terminated. The article is based on the fact, the temperature f ield and stress field of laser deposition repairing of TA15 titanium alloy is researched,A theoretical basis is provided in order to control the residual stress and distortion i n the process of laser deposition repairing.A mathematical model is built for the temperature field and stress field of laser deposition repairing process by using ANSYS. The numerical simulation of temperature field of laser deposition of TA15 titanium alloy is realized by “element birth and death” technology. The influence of laser power, scanning speed, different substrate sizes and subarea-scanning on the temperature of laser deposition repairing, and the change of temperature field and the distribution of temperature gradient of different nodes are analyzed. On the basis of temperature field, the mathematical model of laser deposition repairing of TA15 titanium alloy stress field is built by using coupled thermo-mechanical method.The influences of different process parameters, different scanning paths and repaired substrate preheating on the stress field of laser deposition repairing are analysed, and the reasons are analyzed. Laser deposition repairing experimental system is established, the temperature field of laser deposition repairing is measured by Infrared Thermo-meter, the microstructure of laser deposition repairing is analyzed, finally the residual stress of repairing parts was measured,which is contrast with the simulated results, both are in good agreement.