Study On The Filling Capacity, Microstructure And Mechanic Property Of Thin-walled AlSi10MnMg Aluminium Alloy Component During High Pressure Casting

Energy consumption, emissions and environmental problems, brought by the rapid development of Chinese automotive industry, have promoted the automotive lightweighting, which has became a topic of concern. Die-casting is a special modern metal processing technology of little or no cutting casting methods and a net shape technology and it has been widely used in the forming of aluminum alloy products. In the production of aluminum alloy thin-walled products, alloy liquid flow behavior is one of the most important factors that affects the quality of products.In this article, the AlSilOMg aluminum alloy thin-walled sample was used as the object of study. Using the FLOW-3D casting simulation software to simulate the die-casting, the article analyzed the impact of viscosity, casting temperature and speed of die-casting on aluminum alloy filling ability,which was verified by the die-casting experimental results.Studies have shown that the viscosity values of the AlSi10MnMg alloy was lower with the increasing of temperature, but it was not a linear relationship. When the alloy temperatures was down to the liquidus temperature, the viscosity value suddenly dropped. Before the solidification of the aluminum alloy melt, the impact of the viscosity on the filling length was slight.When aluminum alloy melt started to solidify, the greater the initial viscosity of aluminum melt, the shorter of the filling length and the worse of the filling ability.With the increasing casting temperature, the critical length of sample increased and tensile strength and fracture elongation rate of the sample at the entrance were first to increase and then to decrease. At the temperature of650℃and680℃, tensile strength and fracture elongation rate decreased with the increasing of the filling length. At the temperature of710℃and740℃, tensile strength and fracture elongation rate of sample changed slightly with the increasing of the filling length.With the increasing casting temperature, the stoma of the sample at the entrance was from scratch, the pores shape became from the large-size volume gas-stoma into a diffuse-distribution gas-stoma and the organization of α (Al) dendrite got small.With the casting speed increasing, the filling length growth, density, tensile strength and fractured elongation rate of sample reduced. When injection pressure was20MPa, the casting temperature was680℃and injection speed was300mm/s, mechanical properties of samples was the best. Study found that the specimen pores were first to decrease and then to increase with the increasing of the filling length, α (Al) dendrite changes little.