Study of hot pressed sintering of premixed Al7075 based B4C reinforced composites on wear mechanism

Abstract

Abstract Al 7075 alloy is high strength alloy with excellent physical and mechanical properties. Though the alloy has capacity to work as structural material and many a times poor tribological properties that limits its applications. In this study, efforts are made to improve wear performance of this alloy by addition of B4C from 2 to 20% by weight. Hot Press Sintering (HPS) method was used for synthesis of the composites to achieve maximum densification. The wear tests were carried out on Pin on Disc (POD) machine at various combination of speed (V = 1, 1.5, 2, 2.5 m/s) and load (P = 10, 20, 30, 40 N) with constant sliding distance of 3000 m. These composites were then characterized for hardness and density measurement, Microstructural, EDS and worn out surface analysis. Minimum wear rate was observed for Al7075-10 wt% B4C composite when hot press sintered at 550 0C, 40 MPa for 6 min. The resultant improvement in wear resistance could be attributed to dispersion strengthening due to B4C particulates. It was established that the Archard wear coefficient facilitates in exploring wear mechanism by delineating adhesive to abrasive wear modes.