Investigations on Wear Machinability and Tool Condition Monitoring of Hybrid Alumnium Composites

Abstract

In the last two decades, research has shifted from monolithic materials to composite materials to meet the global demand for light weight, high performance and environmental friendly materials with enhanced properties like strength, wear and corrosion résistance. These composites consist of a ductile metallic matrix reinforced with a dispersion of hard ceramic phase in the form of particulates or fibers to impart additional strength as well as other properties to the material. Commonly used reinforcements include alumina and silicon carbide. These reinforcements have been used by various researchers for improving mechanical as well as tribological properties. A detailed literature review was carried out to decide the choice of matrix and reinforcements for the present study. Accordingly, it was decided to fabricate composites with Al-SilOMg (a heat treatable alloy) with alumina and graphite as reinforcements. Stir casting technique was employed for fabricating three different hybrid composites containing 3 wt%, 6 w1% and 9wr alumina respectively along with 3 wt% graphite particles. Presence of hard alumina particles and soft graphite particles in the aluninium matrix significantly intluence the mechanical, tribological and machining characteristics. Microstructural investigations as well as evaluation