Papers by Author: Ming Fu Fu

Abstract: Base on the coupled three-dimensional model of flow temperature and apparent viscosity on semisolid materials, the mould filling processes of liquid and semisolid magnesium alloys have been analyzed. The simulation results showed that the semisolid mould filling with the characteristic of pseudo-plasticity and Bingham type is steady and the air entrapment is much smaller than that of liquid die casting. Therefore, the semisolid die casting can prevent from those defects produced by the traditional die casting, which offer a new technology for lower interior defects and better quality.

Abstract: The traditional extrusion and thixo-extrusion processes of wrought magnesium alloy were studied with both computer numerical simulation and experimental methods. The thixo-extrusion set-up was made. The constitutive model of semi-solid AZ61 alloy was established in our prior literature. The comparison of two forming processes had been done. Results indicated that smaller load and uniform strain & stress were acquired in thixo-extrusion process. Simulation results were in good agreement with experimental ones.

Abstract: The microstructural structures of SiCp/AZ61magnesium matrix composite were studied in three different casting processes, and their hardness was measured. The results indicated that SiCp/AZ61 composites fabricated in stirring melt casting process, compared to those in fully liquid stirring casting process and in semi-solid stirring casting process, possessed fairly uniform distribution of SiC particulates and few porosity rate. It was an ideal metal matrix composites fabricated process. The Vickers hardness of non-reinforcement AZ61 magnesium alloy is higher than that of semi-solid billet, and the Vickers hardness of SiCp/AZ61 composite is obviously higher than that of the matrix. In the meantime, the Vickers hardness of SiCp/AZ61 composite can be continuously enhanced with an increasing of volume fraction of SiC particles.