Characterization of pine needle ash particulates reinforced surface composite fabricated by friction stir process

The topology of surface is essential for enhancing the tribological performance of material. In the present experimental investigation, the hybrid surface composite was fabricated by incorporating titanium diboride (TiB₂) and pine needle ash (PNA) as reinforcement on the surface of aluminum alloy Al 1120 through friction stir process (FSP). The dry pine needle is an agro waste material, and contains the hard compounds like SiO₂, Al₂O₃, CaO, and Fe₂O₃ as main constituents. The effect of doping of pine needle ash and TiB₂ into fabricated aluminum alloy metal matrix surface composites reported in this paper. The FSP setup was developed on a vertical milling machine and process parameters were selected as tool rotational speed of 1400 rpm and tool feed rate of 56 mm min⁻¹. The microstructures of surface composites were examined through optical microscope. The mechanical properties and tribological behavior were evaluated by using microhardness tester, universal testing machine and pin on disk wear testing tribometer. It was observed that mechanical properties (micro hardness, tensile strength and impact strength) and wear resistance of surface composites improved as compared to matrix material (Al 1120). (paper)