Preparation and Strengthening Mechanisms of Ultrasonic-Assisted Cr3C2 Particle-Reinforced Al Matrix Composite

Abstract

A novelty Al matrix composite reinforced with Cr3C2 particles was prepared by an ultrasound vibration treatment-assisted casting process. The Cr3C2 content on the microstructure and mechanical properties of Cr3C2p/Al composite were researched systematically. The results indicated that Cr3C2 particles were effectively distributed around the grain boundary and led to a great reduction in crystalline size. The density, porosity, and Vickers hardness of the composites rose simultaneously with the increase of Cr3C2 content. Meanwhile, the tensile strength and yield strength increased by 104.5% and 85.7%, respectively by adding 3.0 wt. % Cr3C2. The fracture morphologies showed that the fracture mechanism was plastic fracture for the pure Al and gradually transformed to brittle fracture as the content of Cr3C2 exceeded 3.0 wt. %. Moreover, the strengthening mechanism of the composite was also discussed.