Influence of microwave sintering temperatures on mechanical and microstructural Behavior of Al/SiC/snail shell hybrid composite synthesized through powder metallurgy technique

Abstract

This study emphasizes the synthesis of hybrid aluminum composite reinforced with SiC and Snail Shell (S-Shell) particles through the powder metallurgy technique. The hybrid composite corresponding to the optimized volume fraction of SiC and Snail shell powder (Al-6%SiC-6%S-Shell) was subjected to microwave-assisted sintering (MAS) by varying the sintering temperatures from 400°C to 550°C in steps of 50°C. Results concluded that microwave-sintered composites show superior mechanical characteristics than the composites sintered through conventional sintering techniques. The maximum ultimate tensile strength (U.T.S) of 316 MPa, and compression strength of 396 MPa were obtained for microwave sintered Al-6%SiC-6%Snail shell powder composite sintered at 500°C. However, increasing the sintering temperature above 500°C leads to a reduction in U.T.S and Compression strength due to the formation of coarse grains by absorbing the microwaves at higher temperatures. The U.T.S, Compression strength and Vickers hardness of the microwave sintered Al-6%SiC-6%Snail shell powder hybrid composite sintered at 500°C was enhanced by 42.08%, 42.4%, and 35.5% compared to conventionally sintered hybrid composite. The grain size was found to be increased with an increase in microwave sintering temperature due to the enhancement in the absorption capability of the microwaves with the temperature rise. The results of this study also suggest that choosing materials with a high microwave response helps to achieve improved mechanical properties for microwave-sintered composites.