Molding Process Simulation Of Heterogeneous Material Molding For Selective Laser Melting And Its Equipment Stucture Design

Funtionally gradient materials research has quickly become active project materials research at home and abroad. It is a n ew type of functional composites which is continuously from one side to another. It makesthe properties and function of the material have a gradient change, and overcome the matching factors of different materials. It is mainly used in aerospace field.A new kind of rapid prototyping technology, selective laser melting(SLM) has become one of the most promising manufacturing due to its unique advantages in recent ten years. In the forming process of two different materials at the same time, different forming parameters and the requirements of process are needed because of the different material properties. So forming the two materials put forward special requirements.In this paper, a method of forming the heterogeneous material parts with SLM equipment is proposed, and the main actuator is designed. Then a thorough study on the SLM forming process of two materials is carried on by the method of computer numerical simulation. A temperature field in SLM process has been founded and calculated based on “element birth and death” techniques by combining the phase change and temperature-dependent materials with the transform of element material properties. And the moving load of the laser gauss heart source is realized by using parametric design language(APDL). The finite element model of single layer single channel and multi-layer multi-channel is established, and the forming region is predicted.Based on the results of temperature field, a finite element model for analyzing the stress and strain field in SLM proces s is established by using the thermal coupling method.The evolution law and the distribution of the residual stress of the thermal evolution are analyzed, and the basis for the practical processing is provided.