Thermal Property Database for Investment Casting Shells

Reliable and realistic thermal properties data for investment casting shell molds are required to correctly simulate the solidification and predict the shrinkage. Investment casting shells exhibit several phase transformations during firing and pouring which affect their transient thermal properties. These properties are dependent upon time, temperature and process history. This study presents the thermal properties (thermal conductivity and specific heat capacity) of seven industrially produced ceramic molds using an inverse method in which pure Ni was poured into ceramic molds equipped with two thermocouples (inside the mold cavity and in the shell). MAGMASOFT® software (hereafter known as Software A) was used to simulate virtual cooling curves which were fitted to experimental curves by adjusting the temperature dependent thermal properties of the ceramic mold. The thermal properties data obtained from the inverse method were compared with measurement results from laser flash and the differences were discussed. The dataset thus developed will serve to improve the accuracy of investment casting simulation.