Abstract
The purposes of this study are to develop a technique of numerically simulating the hardness of a FC250 gray cast iron brake disc casting and verified by experimental measurements. As the numerical model is proven reliable, numerical experimentation is then conducted to homogenize the hardness distribution of a brake disc to obtain better casting quality. The Oldfield’s model was adopted to simulate the nucleation and grain growth during solidification of the casting. A calibration brake disc casting was first made. By comparing the hardness of the calibration brake disc casting with the simulated results using different nucleation and growth coefficients (Ae,Be) in Oldfield’s model, the most appropriate set of values for Ae and Be was obtained. Then, this set of values was applied to the hardness simulation of a test brake disc casting and confirmed by experimental measurements. Through this approach, a set of nucleation and growth coefficients was obtained for the brake disc casting. Subsequently, numerical simulations were conducted for the brake disc casting with different shake-out times to evaluate its distribution of hardness and an optimized shake-out time was then proposed based on the simulated results. The predictions of hardness were validated by comparison with experimental measurements and actual track testing.
