Study Of Numerical Simulation And Design Of Die-casting Mould For Magnesium Vehicle Parts

After analyzing the distance between domestic die-casting mold CAD/CAE techniques and the world﹐s most advanced ones ,and problems demanding prompt solution in this field, the author suggests an idea of integrated die-casting mold CAD/CAE, and wants to practice the idea for a typical die-casting part-Shell-Gear-Change-Lever with actual example. The research is mainly on the realization of Shell-Gear-Change-Lever's die-casting mold CAE and the establishment of standard mould bases. First, according to the specific solidification property of magnesium alloys and the opacity of the metal mould, the solid feature and the surface mesh of the magnesium die casting was made through the Pro/E. ProCAST was used to simulate physical properties of the Shell-Gear-Change-Lever's mold filling process. The corresponding results show that the mainly defects during casting are air holes and shrinkage with using die-casting techniques to manufacture the Shell-Gear-Change-Lever. The formation of air holes could be attributed to that the air could not be successfully discharged from the die. Thus, the air is engulfed and extruded into the casting by the alloy melt with high pressure and flowing speed,then the air inside casting congregates and finally becomes the air holes. The appearance of the air holes would lead to the decrease in mechanical properties and gas tightness of Shell-Gear-Change-Lever. Modified projects of gating systems and flooding systems for die-casting mold were proposed according to the simulation result. The related models were rebuilt and the simulation was carried out again. The optimum project was achieved. The result shows that a great improvement can be achieved and the quality of the Shell-Gear-Change-Lever. This implies that the computer simulation techniques possess a satisfactory capability of reproducing the actual die-casting process and significance in guiding die-casting process design. Based on the Pro/E and its relative functions , an analysis was made to abstract the common characteristics of the standard mould bases of die-casting moulds and make clear the structure of the standard mould-base database. A 3D database of the standard mould bases of die-casting moulds was established. An example of mould design illustrated the standard mould-base database has very well practicability when the database was used in the design of die-casting moulds.