Analysis of Cooling Curves, Microstructure and Properties of Chill Cast Al-B_4C Composites

摘要

The cooling rate depends on the properties of the mold material which has significant influence on the formation of microstructure and in turn on the properties of the cast components. This work is aimed at preparing the Al-B_4C composite using different chill materials by gravity die casting and recording the casting temperature during pouring and subsequent solidification to analyze the cooling rate of the casting. The effect of chilling on the microstructure and mechanical properties are determined. The cast specimens are cut and polished by standard metallographic procedure. Optical micrographs are taken at different magnification to reveal the microstructure and B_4C particulate distribution. The micro hardness and tensile test results indicate that there is a significant increase in these properties with the increase in B_4C content.