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This study investigated on thermal deformation of AC4C aluminum alloy casting material for tire mold built in metal casting method. In this study, temperature, displacement and stress distributions of AC4C casting material occurred inside the mold were numerically calculated by finite element analysis (FEA). Also, temperature profiles of AC4C were experimentally measured to investigate the temperature characteristics during the solidification process in metal casting device. The result of this study revealed that the numerical result of temperature profiles predicted a rapid cooling from initial state to about 25 minutes, but the experimental result of it uniformly occurred from initial state to about 15 minutes by the phase change. However, the cooling patterns of two cases were almost similar results in the whole cooling process. Also, thermal deformation was generated by the difference of cooling temperature between the surface and inside of the casting from the results of displacement and stress distribution predicted by FEA.

In the process of interpreting simulation results, new post-processing techniques are developed. This work presents a post-processing method that analyzes the solidification pattern formed by simulation of the solidification process of molten metal in a mold to produce shaped castings. Simulations generally involve numerical solutions of differential equations which are discretized by dividing the three-dimensional computational domain into small finite volume elements using a 3D grid. The locations of the grid points and values of the solidification time at these locations are used to divide the spatial data into 3D sections such that starting from a hotspot location within the section that has high solidification time, there is a gradient outwards with lower values of solidification time. Each section is assumed to be fed by one or more feeders that must freeze only after the section has solidified completely. The volume of a feeder can be determined from the volume of the section it is supposed to feed. The volume and surface area of sections are determined approximately to calculate feeder size and dimensions. The post-processing algorithm is a simulation-based quantitative approach to feeder design which in conventional foundry practice has been more of an art than science. It is also general enough for use in other 3D segmentation applications.

A kind of permanent mold coating for magnesium alloy was developed using magnesia powder and diatomite as refractory aggregate. The properties of the coating were tested and analyzed by various ingredients. The final ingredient was determined through the tests which are to find out the optimal proportion of two kinds of aggregate and the influences to coating properties by changing the proportion of binder and suspending agents. The experimental results shown that the permanent mold coating performed good properties on magnesium alloys when the optimized ratio of magnesia powder and diatomite was 6: 4, and the integrated property is very excellent when the coating was prepared with 2 percent of sodium bentonite, 0.4 percent of CMC, 7 percent of sodium hexametaphosphate, and 7 percent of sodium silicate. The excellent performance has also been proved by actual casting test.