Effect of processing speed on wear and corrosion behavior of novel MoS2 and CeO2 reinforced hybrid aluminum matrix composites fabricated by friction stir processing

Abstract

The extensive use of aluminum matrix composites as structural material urges it to possess good surface properties such as wear and corrosion resistance. To achieve that, mixture of MoS 2 and CeO 2 powder was reinforced in Al7075 alloy through friction stir processing with different processing speed and multi-pass approach. The microstructural image analysis by optical microscope and scanning electron microscope revealed reduction of matrix grain size and improvement of particle distribution for lower processing speed and multi-pass processing. The elemental analysis indicated well dispersion of reinforcement particles in matrix along with the presence of compounds of aluminum alloy. The microhardness and tensile strength were increased with reduction of processing speed and increase of number of pass. The friction coefficient and the wear loss were also low for composites produced with low processing speed and multi-pass. A combined abrasive and adhesive wear was observed in all the processed composites. With increase of processing speed and number of pass, the corrosion behavior of the composites in 3.5% NaCl solution deteriorated. The composite produced with 30 mm/min and 2 pass exhibited best particle distribution, microhardness and wear resistance. However, the composite fabricated with 30 mm/min and 1 pass yielded best corrosion resistance. • Novel hybrid aluminum matrix composites developed by friction stir processing • Microstructure of the fabricated composites analyzed • Microhardness distribution measured • Wear mechanism and friction coefficient variation analyzed and effect of processing speed on wear loss discussed • Corrosion behavior and effect of process parameters on corrosion parameters discussed