Microstructure and compressibility of SiC nanoparticles reinforced Cu nanocomposite powders processed by high energy mechanical milling

Cu/SiC nanocomposite powders with homogeneously distributed nanosize SiC particles were produced by high energy mechanical milling (MM). Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and micro-hardness and density measurements were performed to understand the effects of microstructure and hardness on compaction behavior during MM. The effects of SiC nanoparticle content and mechanical milling time on apparent density (AD) and tap density (TD) of the nanocomposite powders were systematically investigated. The Hausner ratio (HR), defined as TD to AD, were estimated to evaluate friction between the particles. Increasing MM duration and SiC content resulted in a decrease in HR due to the changes in morphology and hardness of the powders. Additionally, the compressibility behavior of the powders was theoretically examined using a compaction equation to investigate the deformation capacity. Densification parameters of the nanocomposite powders showed a significant decrease with increasing MM duration and a slight decrease with increasing SiC content.