Wear behavior of conventional and spark plasma sintered Al2O3-NbC nanocomposites

Abstract

[EN] This study aims to investigate the dry sliding wear behavior of Al2O3-5vol.% NbC nanocomposites sintered by two different consolidation techniques: conventional sintering (CS) and spark plasma sintering (SPS) at temperatures ranging from 1450 to 1600 degrees C. The dry sliding wear tests were performed on a tribometer with a ball-on-disc configuration using an Al2O3 ball as a counterpart material, with a normal contact load of 15 and 30 N, a sliding distance of 2000m and a sliding speed of 0.1m/s at room temperature and ambient environment. The sintering methods, mechanical properties and applied load acted directly on the wear mechanism of the nanocomposites. The samples sintered by SPS exhibited higher densification and hardness, in addition to a lower friction coefficient and wear rate. Based on the wear rate, these nanocomposites exhibited a moderate regime with 15N of load, and several regimes when 30 N of applied load was used. The main wear mechanisms observed were plastic deformation, abrasion and grain pull-out. The excellent results show that Al2O3-NbC nanocomposites are ideal for the manufacture of new products such as cutting tools.