Microstructural and mechanical characteristics of AA2014/SiC surface composite fabricated by friction stir processing

Friction stir processing is a novel technique for fabricating surface composites with variety of reinforcements. Aluminum alloy AA2014 surface composite is fabricated by reinforcing silicon carbide particles at a constant rotational and traverse speed of 710 rpm and 100 mm/min., respectively. Recrystallized equiaxed microstructure developed due to occurrence of dynamic recrystalliztion during friction stir processing. Defect free surface composite with uniform distribution ofSiCparticles is fabricated. The reinforcement particles size reduction is also observed during processing. However, the hardness of friction stir processed alloy is reduced as compared to base alloy indicating major role of precipitation hardening than grain refinement. The surface composite shows increase in hardness due to incorporation of harder ceramic particles. (C) 2015 Elsevier Ltd. All rights reserved.