Silicon (2016) 8:591–599 DOI 10.1007/s12633-016-9437-5 ORIGINAL PAPER Tribological Characterization of Stir-cast Aluminium-TiB 2 Metal Matrix Composites Suswagata Poria 1,2 · Prasanta Sahoo 1,2 · Goutam Sutradhar 1,2 Received: 3 March 2016 / Accepted: 11 April 2016 / Published online: 20 April 2016 © Springer Science+Business Media Dordrecht 2016 Abstract The present study considers friction and wear of aluminium matrix composites reinforced with TiB 2 micro particles processed through the stir casting method rather than in-situ techniques adopted by earlier studies. Different weight percentages of TiB 2 powders having average sizes of 5 - 40 micron were incorporated into molten LM4 alu- minium matrix by stir casting method. The friction and wear behavior were studied for Al-TiB 2 composites prepared according to specific dimensions by using a block-on-roller type multi-tribotester at room temperature. Normal loads of 25 - 75 N and rotational speed of 400 – 600 rpm were used for determination of friction and wear behavior. It is found that friction and wear decrease with increase in percentage of TiB 2 reinforcement in the composite, while friction and wear increase with applied load and speed. Scanning elec- tron microscopy studies reveal the presence of both abrasive and adhesive wear mechanisms with abrasive wear being predominant. Keywords Al-TiB 2 composites · Hardness · Friction · Wear  Prasanta Sahoo psjume@gmail.com; psahoo@mech.jdvu.ac.in 1 Department of Mechanical Engineering, Jadavpur University, Kolkata 700 032, India 2 Centre of Excellence on Phase Transformation and Product Characterization, TEQIP-II, Jadavpur University, Kolkata 700032, India 1 Introduction Metal matrix composites (MMCs) have been an active area of research and scientific investigation for last two decades but only in recent times, MMCs have become realistic engi- neering materials [1]. In metal matrix composites, two or more different phases (one of which is metallic phase) co- exist and are suitably distributed to provide some important properties which cannot be achieved by either of the individ- ual phases [2, 3]. Metal matrix composites consist of metals or their alloys as matrix phase and continuous or discontin- uous fibers, whiskers or particles as reinforcement. Com- bination of matrix and their reinforcements and controlling the procedure of synthesis allow to produce some unique combination of properties in MMCs like fatigue strength, damping property, electrical and thermal conductivity, low friction, wear resistance, suitable expansion coefficient etc. which cannot be achievable in any monolithic metal or alloys [4]. Among MMCs, composites based on aluminum (Al) alloys are the largest share of the volume produced for commercial applications [5]. For applications in automo- tive and aerospace industries, aluminum matrix composites are now-a-days first in league due to its high strength to weight ratio, light weight and good tribological ranking which lacks in sole aluminum as metal or alloys [6]. Al alloys have already been replaced by aluminum matrix com- posites (AMCs) in many applications where tribological properties are of important consideration [7–9]. In appli- cations like ground transportation, thermal management, aerospace industry, automotive industry, recreational indus- tries, high structural efficiency and excellent wear resistance are the most needed properties and AMCs fulfill those requirements in engineering materials [10]. Improvement