타이어 몰드용 AC4C 주조재의 온도분포 및 열변형 예측에 관한 연구

Abstract

The present study was numerically and experimentally investigated on the temperature distribution and thermal deformation inside the automobile tire mold using the AC4C casting material. In this study, the AC4C casting material, one of the Al-Si-Mg system aluminum alloy, was selected as a casting material and the metal casting device was used in order to manufacture the mold product of automobile tire in the actual industrial field. For the numerical analysis, "COMSOL Multiphysics 3.3 Ver", the commercial program based on the partial differential equation (PDE), was used in order to predict the thermal deformation of the AC4C tire mold including temperature, displacement and stress. Also, the prototype was produced from the result of numerical analysis and the experimental study was performed to measure the temperature distribution inside the tire mold during the cooling process. The numerical result revealed that the temperature distribution inside the mold occurred rapid cooling from the initial cooling to 20 minutes. And then, it was slowly cooled after separating the mold in metal casting device and the completed cooling time of casting mold took about 7 hours. Also, the results of displacement and stress distributions appeared to be larger at the center parts of tread part in mold than on its sides because of the shrinkage caused by the cooling speed difference. Moreover, when the profiles of the temperature distribution were experimentally measured and were compared with those of the numerical result, it appeared that there was a slight temperature difference because of the latent heat by phase change heat transfer. However, the result of cooling temperature and patterns were almost similar except for the latent heat interval.