Effect of TiB2 on the mechanical and tribological properties of marine grade Aluminum Alloy 5052: An experimental investigation

Abstract

Aluminum Alloy 5052 is one of the excellent corrosion resistant alloys among the Aluminum 5000 series alloys. Despite the favourable corrosion resistance, it exhibits low resistance to wear and perform poorly in various tribological applications. This study attempts to investigate the impact of TiB2 reinforcement on the mechanical and tribological properties of Aluminum Alloy 5052 matrix alloy, fabricated using the stir casting technique. Composites with varying weight percentages (0, 2.5, 5 and 7.5 wt %) of TiB2 were prepared. Vicker's hardness testing was conducted to assess the effect of TiB2 content on composite hardness. Hardness of composites increased from 65.5 to 85.16 HV in tandem with the TiB2 content depicting a rise of about 30 %. Tribological properties were studied through dry sliding wear tests using a pin-on-disc tribometer, with varying loads (10 N and 50 N) and sliding speeds (1 m/s and 3 m/s). The results demonstrate that the addition of TiB2 significantly improves the wear resistance of the composites, being optimum in composite with 5 wt % of TiB2. A maximum increase of about 36 % in wear resistance was observed at high load and high-speed conditions corresponding to 5 wt % TiB2 concentration. FESEM analysis revealed distinct wear modes and the role of TiB2 in changing the wear mechanism from abrasion to delamination. This study underscores the pivotal role of TiB2 in enhancing the mechanical and tribological properties of Aluminum Alloy 5052, expanding its application scope, particularly in lightweight engineering applicationsin general and marine in particular.