Effect of SiC Particles Dispersion on the Grain Size and Mechanical Properties of Cu/SiC Metal Matrix Nanocomposites Produced via MFSP

Abstract

Friction stir processing (FSP) has been found as a promising method for surface modification of materials such as grain refinement and hardness increment. FSP is also widely used for fabrication of in situ micro-and nanocomposites on the surface of materials. In this research FSP is used for inserting the nanosized SiC particles into the copper matrix. Subsequently, 4-pass FSP is applied to obtain good dispersion of SiC particles in copper matrix leading to improve the mechanical properties of the fabricated composite. The optical microscopy and scanning electron microscopy are used for microstructural evaluation. Results show that an increase in the number of FSP passes considerably enhances the dispersion of the SiC particles in the stir zone and also breaks down the SiC particles. These phenomena lead to reduction of the grain size and improvement of mechanical properties in 4-pass composite compared to that of fabricated by 1-pass FSP.