Experimental Studies on Mechanical Characterizations of Silicon Nitride and Alumina added Al7075 Hybrid Composite for Various Engineering Applications

The present investigation is aimed at studying the influence of alumina and silicon nitride reinforcement particles in addition to the Al 7075 alloy on the hardness, wear, tensile, and impression creep behaviour. Three different composite specimens such as Al 7075 + 5 % alumina, Al 7075 + 5 % Silicon nitride, and Al 7075 + 2.5 % Silicon nitride + 2.5 % Alumina were fabricated using a stir casting process and the prepared composites were subjected to hardness, dry sliding wear test using pin on disc tribometer, tensile testing and impression creep tests. From the results, it was observed that the hardness of the Al 7075 alloy increases with the addition of both silicon nitride and alumina and Al 7075 + 2.5 % Silicon nitride + 2.5 % Alumina exhibited the maximum hardness of the composite specimens. Al 7075 + 2.5 % Silicon nitride + 2.5 % Alumina showed a 75% increase in wear resistance in comparison with the Al 7075 alloy and it also shows an improvement in creep and tensile properties.