Mechanism And Experimental Study Of Thermal Deformation From Laser Brazing

Since early twentieth century, the United States Scientist Einstein has found laser. Then the laser has played a more and more important role in industrial practice. The laser processing as a kind of indispensable process method is applied to many engineering industry. Laser brazing technology which is a very important kind of applications of laser, is usually used for precise welding, and can control artifacts’thermal deformation after welding to a smaller tolerance.Gear-honing-tool which is the main tool of gear honing processing, can do precise machining of hardened gear surface. Gear-honing-tool is manufactured mainly by using electroplating process at present, and this method can be improved in many respects. Now a new processing method which the laser brazing is used to make gear-honing-tool is presented, and the precise of the gear-honing-tool could be improved. But in the process of brazing, the rapid temperature change will make the tool matrix generating the thermal-elasticity, the thermoplastic deformation. The residual thermal deformation of the tool after cooling will have an impact on its fabrication precision. So to pursue the mechanism and the deformation regularity of the tool in the condition of the laser heat source inputting, is particularly important.In this paper, the heat process of laser has been simulated with the SYSWELD software to the steel plate and the gear-honing-tool tooth. The experiments of the thermal deformation have been carried on. and the main work is as follows:1. The laser brazing, laser heating and the related literature was consulted, and the research methods and achievements of the study about stress and strain distribution, hardness distribution, overall deformation distribution after cooling of artifacts of the thermal process by using laser as a heat source was study.2. Through deriving the motion equations of thermal elastic mechanics, strain equations, dynamic equations and stress strain constitutive equations were made column equations to solve a particular point’s deformation displacement, so as to get the deformation contour of work piece with known of the temperature contour distribution, the boundary conditions and the premier conditions of the workpiece.3. The thermal process and deformation of the steel plate heated by laser was analyzed by the use of a series of SYSWELD software. And the mechanism of the distribution of temperature and thermal deformation of the steel plate under the condition of different heat source loading trajectory and different thickness of the steel plate was study through finite element simulation.4.The experiment of laser scanning on steel plate was conducted by using laser welding machine, and the study of the relationship between the deformed angle and laser heat source movement speed, laser facula diameter, laser power input was carried on to find their internal relations.5. The finite element simulation of thermal process of gear-honing-tool heated by laser was conducted. The moving heat source was loaded on the complex surface. Temperature distribution and deformation distribution of the gear-honing-tool tooth heated by heat source in different loading methods were analyzed, and further study of the relationship between the tooth deformation and the laser heat source movement speed, the diameter of laser facula, laser power input was carried on to find their internal relations.6. Reviewing the thesis, and present many disadvantages existing in this research. Put forward the direction of further research, and look forward to the content of the subject.