Gas Mediyn EDM Surface Strengthening Finite Element Numerical Simulation

With the research on EDM teehnology, EDM technology application scope is increasing widely. Using its processing principle, EDM technology has been successfully applied to the surface strengthening technical fields, and realized the electrode material in gas medium in the deposition.It is a great breakthrough of the traditional processing methods, greatly enriched connotation of EDM technology, which breaked the previous people for this technique in the limitations of EDM. It has important significance for the development of technology progress.This paper summaried EDM surface strengthening technology and its numerical simulation development and achievements. And then studied in gas medium in the realization of EDM surface condition. Analysised polarity, working medium, energy of electrode distribution between electrodes, electrode materials of thermal constants and energy accumulation that affect the results of EDM surface strengthening in gas medium.Next it analysised and expatiated the basic theory and numerical simulation analysis method of the temperature field and stress field, heat transfer model, heat source model, boundary conditions, the thermal stress of mechanical criterion, establishment of finite element equations in EDM surface strengthening. In order to improve the calculation accuracy, the paper selected physical proper parameters on high-temperature and refine the surface grid of workpiece. Gaussian function heat model was selected and through step-by-step load approach to the electric heat surface moving. Then through the post-processing, this paper gave EDM surface strengthening temperature field and stress field of the dynamic variation and result analysis. Finally, through the analyses it indicated that by selecting appropriate conditions and processing time can obtain certain thickness and high hardness strengthened layer.It maked the surface quality of the workpiece got obvious improvement.This paper provided theoretical basis and guidance for different forms of surface strengthening temperature field and stress field analysis. Promoted the finite element method in EDM surface strengthening mechanism reseach, as well as in practical engineering applications. It can provide theoretical basis for further optimizing the strengthening technology and provide the conditions for expanding the application areas of this technics.