Pressure-driven mold filling model of aluminum alloy melt/semi-solid slurry based on rheological behavior

Publication date: Available online 20 September 2019Source: Journal of Materials Science & TechnologyAuthor(s): Zhen Ma, Huarui Zhang, Wei Song, Xiaoyan Wu, Lina Jia, Hu ZhangAbstractThe pressure-driven mold filling ability of aluminum alloy melt/semi-solid slurry is of great significance in pressure casting processes, and the rheological behavior of the alloy has a crucial effect on the mold filling ability according to fluid dynamics. In this work, a pressure-driven mold filling model is first proposed based on the rheological behavior of the alloys. A356 alloy is employed as an example to clarify the rheological behavior of aluminum alloys, which obeys the power law model and is affected by temperature. The rheological behavior of the alloy in semi-solid state is modelled with the coupling of shear rate and temperature. The stop of mold filling attributes to the pressure loss which is caused by the viscosity during the flow of the melt/semi-solid slurry. Pressure loss caused by viscous flow and heat transfer between the alloy and the mold are calculated and coupled during the mold filling of the melt/semi-solid slurry. A pressure-driven mold filling model of aluminum alloy melt/semi-solid slurry is established based on steady-state rheological behavior. The model successfully predicts the filling length of melt/semi-solid slurry in pressure casting processes. Compared with the experimental results, the model can provide a quantitative approach to characterize the pressure-...
Source: Journal of Materials Science and Technology - Category: Materials Science Source Type: research