Determination of thermophysical parameters in numerical simulation of rheo squeeze casting

The process of filling and solidification of 7075 aluminum alloy wheel parts in squeeze casting was simulated by AnyCasting software. The effects of filling speed, melt temperature and mold preheating temperature on the parts were analyzed. The causes of defects were analyzed, and the corresponding process improvement measures were put forward.

(a) Thermal conductivity; (b) Density;
(c) Fraction solid; (d) Dynamic viscosity

The alloy material used in the test is 7075 aluminum alloy, and the temperature range of solid-liquid phase is 475 ~ 635 ℃. After actual detection, its composition meets the national standard GB / t3880.2-2006. According to the standard, the relevant physical parameters are input into AnyCasting software, and the curve of thermophysical parameters of 7075 aluminum alloy with temperature is obtained through material analysis, as shown in the figure.

It can be seen from the figure that the thermal conductivity decreases with the increase of temperature, decreases sharply at about 600 ℃, and then rises slowly; the density decreases with the increase of temperature, and the curvature changes; the fraction solid decreases with the increase of temperature until it is liquid; and the dynamic viscosity decreases with the increase of temperature.