Fabrication and property evaluation of Al 6061 + x% (RHA + TiC) hybrid metal matrix composite

Abstract

The present work aims in understanding the mechanical properties and strengthening behavior of Al 6061 based particulate hybrid aluminium matrix composites (PHAMCs) reinforced with rice husk ash (RHA) and TiC particles (sizes; 10 µm) fabricated by liquid metallurgical route. RHA + TiC particles (3 wt%, 5 wt%, 7 wt%, and 9 wt%) are added in equal proposition in the hybrid composite which is fabricated through stir-casting technique. Samples are named as S1, S2, S3, S4 based on the proposition of RHA and TiC, whereas Al 6061 alloy is casted and named as S0. Fabricated composites were homogenized at 400 °C for 1 h and then aged to 115 °C for 24 h. X-ray diffraction result confirms the presence of principle elements like Al, TiC, Si and oxygen without the formation of any intermetallic elements. Property of PHAMCs such as ultimate tensile strength, yield strength, and micro Vickers hardness had improved by 31%, 17.1%, and 18%, respectively with increase in the percentage of reinforcement. Addition of reinforcement slightly lowers the mechanical properties of PHAMCs which is due to agglomerations and porosity. Reinforcement with more than 7% of RHA and TiC in matrix significantly effect the density, impact energy and percentage of elongation to a maximum of 3.88%, 28.52%, and 29.91%, respectively. Microstructure of the fractured surfaces are analysed through SEM and it is reported.