Evaluation of fatigue and impact behavior of titanium carbide reinforced metal matrix composites

The objective of this work is to evaluate the load bearing behavior of titanium carbide reinforced aluminum matrix composites and their suitability for automotive application. Three different weight percentages of TiC particulates: 10, 12 and 15, in the size of 325 meshes were prepared by stir casting process to study the effect of particulates for load bearing application. Tensile, fatigue and impact tests were conducted on the ASTM standard test samples to investigate the effect of titanium carbide in Al-Si matrix alloy. XRD analysis shows various intermetallic phases present in the composites cast at 750 °C. Crack propagation and failure mechanism of the fabricated composites were examined using SEM. The steering knuckle used in automobile suspension system is a critical structural component subjected to both fatigue and impact load during its service and it is considered in this study. The steering knuckle made of Al/TiC, unreinforced alloy and spheroidal graphite (SG) iron was tested and compared for the performance in real time load conditions. The results show that performances of samples and component knuckle were remarkably increased in the presence of TiC reinforcement. Fractographs show that cyclic load starts the crack initiation from the matrix region and particle breaking mechanism occurs during impact load.