Influence of rare earth particulate on the mechanical & tribological properties of Al-6063/SiC hybrid composites

Abstract

Mechanical characteristics and tribological behavior of aluminum (Al6063) matrix composites (AMCs), fabricated using different compositions of SiC particles and mixed rare earth particulates (REP) were investigated. The hybrid composites samples were fabricated via bottom pouring casting route by varying 3, 6, and 9 wt.% of SiC and 1, 2, and 3 wt.% REP(CeO₂+La₂O₃) mixture. Microstructural examination was conducted using electron back scattered diffraction (EBSD) and scanning electron microscope (SEM) analysis. Also the elemental composition of the samples was determined by using energy dispersive spectroscopy (EDS). The microstructural studies revealed uniform dispersion of REP (CeO₂+La₂O₃) throughout the Al6063 matrix which promotes grain refinement. Mechanical properties such as micro-hardness, impact strength, ultimate tensile strength, percentage elongation, along with tribological properties such as wear rate were investigated on AMCs at room temperature. The outcomes concluded that incorporation of up to 2 wt.% of REP mixture resulted in superior hardness, impact strength, tensile strength and lower wear rate along with marginal improvement in percentage elongation. However, a decrement in mechanical properties and specific wear rate was observed on increasing the REP mixture to 3 wt.%.

Keywords:

• Lanthanum
• rare earth particulate
• tribological
• microstructure