An investigation on mechanical and wire electrical discharge machining characteristics of magnesite reinforced aluminium 6061 composites

Abstract

Employing natural materials as reinforcement particulates in newlineAluminium-based Metal Matrix Composites (AMMCs) has started as a newlineconsequence of growing awareness of environmentally friendly newlinemanufacturing practices. In this direction, the magnesite materials are newlineexcellent sources of magnesium oxide (MgO) and can be an excellent newlinereinforcement material for making sustainable AMMCs. Therefore, different newlinegrades of magnesite powders i.e. Dead Burnt Magnesite (DBM), Lightly newlineCalcined Magnesite (LCM) and Waste Magnesite (WM), are used as newlinereinforcement particulates to fabricate Aluminium 6061 composites through newlinestir casting route. In terms of chemical properties, the LCM is activated while newlinethe DBM is inactive. The LCM and DBM possess very high magnesia newlinecontent. With some sand and vast dust particles, WM powders contain 8% newlinemagnesium. These powders contain compounds like chromium and copper in newlineaddition to SiO2, MgO, and Al2O3. The particle sizes of LCM powders varied newlinefrom 0.5375µm to 14.1375µm. The average particle size of DBM is newline2.0588µm, while that of WM is 1.5159µm. Aluminium 6061 composites were newlinefabricated with the different weight fractions (2.5%, 5%, and 7.5%) of LCM, newlineDBM and WM particles. Good wetting between the magnesite particles and newlinethe 6061 aluminium matrix is confirmed. The microstructure consists of newlinerounded magnesite grains sparsely bound in the 6061 aluminium alloy. The newlinesubrounded to rounded magnesite grains are interconnected with the newlinealuminium matrix. newline