Susceptor-Assisted Rapid Microwave Sintering of Al-Kaolin Composite in a Single-Mode Cavity

The present research addresses the low-temperature sintering of 4% kaolin clay reinforced aluminium composite using susceptor-aided microwave sintering at 2.45 GHz frequency. Kaoline clay the naturally available mineral in the north-eastern regions of india. The study aims to convert this kaoline clay into the value added product with enhanced mechanical properties. The Al-x% Kaolin (x = 2, 4, 6, 8, 10) composite was fabricated through the powder metallurgy process by the application of 600 MPa compaction pressure. The composite corresponding to optimum ultimate tensile strength (U.T.S) was subjected to single-mode cavity microwave-assisted sintering by varying the sintering temperatures as 500°C, 550°C and 600°C. The effect of incorporating kaolin clay on the dielectric characteristics of composite powders, as well as the effect of sintering temperature on the microstructural changes and mechanical characteristics of Al-4%Kaolin composites were also examined. Results concluded that the addition of 4 wt% kaolin powder improves the dielectric characteristics of the composite powder. The maximum Hardness. Compression strength and U.T.S of 97 Hv, 202 MPa and 152 MPa respectively achieved for the Al-4% Kaolin composite sintered at 550°C. The higher fracture toughness of 9.56 Ma. m1/2 reveals the ductile fracture for the composite sintered at 550°C.