Computer Simulation Of Magnesium Alloys Die Casting Processes And Application In Engineering

In this paper, the filling and solidification simulation were done with the aid of Flow-3D software. The magnesium alloys die casting referred in this paper was 480sc engine cover. Simulation comprises pre-process, solver process and post-process, and the pro-presses is an important process. The 3-D geometrical entity should be imported into the simulation software fist. Then the proper meshing should be done according to the die-cast features in order to avoid the incompletion or the increase of the mesh quantities, increasing simulation time of CPU. The boundary conditions and process parameters should be determined subsequently. The simulation could be done. Range of different processing parameter were selected, and range of injection velocity is form 4.3 m/s to 7.8 m/s, range of mould temperature is form 180℃, to 220℃, and the range of pouring temperature is form 680℃to 720℃. The impact of the injection velocity, mould temperature, and pouring temperature on filling time, defect concentration, and CPU calculating time. Injection velocity with 6 m/s, mould temperature with 220℃, and pouring temperature with 700℃should be determined according to the result of orthogonal experiment.Different injection velocity such as 4.3 m/s, 6 m/s, and 7.8 m/s should be applied to the simulation of filling processing and solidification processing. In filling processing, we can compare the impact of difference injection velocity on flowing condition of Mg-alloy, and determine that choosing conformable injection velocity can obtain better filling result. In solidification processing, the impact of difference injection velocity on solidification processing and defect concentration be compared. According to the filling processing, we can analyse cause of forming defect, such as that slowly injection velocity go against supplement feeding, and fastly go against heat conductivity.According to the simulation technology, we can determine forming mechanics and position of flow mark, corrugation, shrinkage porosity in solidification processing. The simulation result tallies with actual die-casting result, so actual reappearance capacity of the simulation software of Flow-3D be validated.Mechanical property of 480sc engine cover die casting is thatσ_b=221～224 MPa,σ_s=169～185 MPa, HBS=87～112, satisfy the request of Chery Company. Structure of die casting is dense, fine grain size. Fractograph is mixture of ductile rupture and cleavage fracture.