ARTICLES Performance enrichment on tribological characteristics of powder metallurgy processed aluminium particulate composites by inclusion of rutile (TiO 2 ) C. Antony Vasantha Kumar a),b) Department of Mechanical Engineering, Scad College of Engineering and Technology, Tirunelveli-627 414, Tamilnadu, India J. Selwin Rajadurai Department of Mechanical Engineering, Government College of Engineering, Tirunelveli-627 007, Tamilnadu, India S. Sundararajan Department of Mechanical Engineering, Scad College of Engineering and Technology, Tirunelveli-627 414, Tamilnadu, India (Received 21 February 2016; accepted 9 June 2016) A novel approach of powder metallurgy processed, cost-effective, environmentally friendly material, rutile, is proposed as an alternate to the conventional titanium-di-oxide (TiO 2 ) in the process of enhancing tribological behavior of aluminium (Al) based composites. Rutile, also possess good thermal stability which is essential for any material subjected to high temperature applications. The role of rutile (TiO 2 ) in the enrichment of tribological and microhardness properties of aluminium based metal matrix composites is presented. Al matrix composite was reinforced with rutile (TiO 2 ) to the proposed compositions (0, 4%, 8%, 12%, mass fraction) through powder metallurgy route. Wear test was done using pin-on-disc apparatus under dry sliding conditions. The preforms were then characterized using optical microscopy (OM), scanning electron microscope (SEM) and energy-dispersive x-ray spectrometer (EDS). Outcomes suggest that to increase in mass fraction of TiO 2 , sintered density of the preforms approaches the theoretical density. OM images ratify uniform dispersion of TiO 2 implants within the Al matrix. TiO 2 offers promising wear and microhardness properties to the proposed composites which attribute to a high dislocation density of deformed planes. Plastic shearing, in conformity with the propagation of shear cracks broke particles as loose fragments which reduces the effective area of contact between the sliding surfaces and reduces loss of material in Al–12% TiO 2 composite. Mechanism of wear disclosed through SEM images and EDS patterns concludes that delamination and adhesion dominates the material removal. I. INTRODUCTION In recent years, exploration in particulate reinforced aluminium matrix composites (AMCs) has been carried out by many researchers due to their superior specific properties. 1–5 Reinforcements in the form of particles are deliberated because they exhibit isotropic material properties and good formability. 6,7 Aluminium based composites operated under high temperature will subject to oxide wear. Inclusion of suitable oxide reinforcement will form a protective layer which constrains direct contact of metals thereby reducing material loss. Aluminium is potentially reinforced with hard and soft materials like SiC, Al 2 O 3 , TiC, TiB 2 , graphite, mica, etc. 8,9 Preceding outcomes of various researchers explored that hard reinforcements show good wear, corrosion, and seizure resistance at high sliding velocity but at the expense of poor machinability whereas soft reinforcements with low friction characteristics improves machinability. Hence, aluminium is hybrid- ized with both hard and soft phases to accomplish enhanced mechanical and wear properties along with improved machinability. 10–12 However, availability, cost, and environmental facets limit the applications of the above as reported by Bodunrin et al. 13 Identification of an appro- priate strengthening material which clenches good mechan- ical, wear, & machinability properties, readily available and environment supportive is therefore essential. Rutile, a natural mineral, rich in TiO 2 , is extravagantly available, economical, and environment receptive material. Contributing Editor: Jürgen Eckert a) Address all correspondence to this author. e-mail: findvasanth@gmail.com, anto_vasanth@rediffmail.com b) Permanent Address: 3D/1, Kirubakaran Street, Military Line, Palayamkottai, Tirunelveli-627002, Tamilnadu, India. DOI: 10.1557/jmr.2016.247 J. Mater. Res., 2016 Ó Materials Research Society 2016 1