Wear behaviour of α- and α/β-SiAlON ceramics stabilized with Nd2O3 and Y2O3

α- and α/β-SiAlON compositions, doped with Y2O3 or Nd2O3, were densified by gas pressure sintering (GPS). The wear and mechanical properties of the materials were investigated and compared to β-Si3N4 materials. Microstructure evolution and its change with composition as well as the influence of the microstructural changes on the mechanical and tribological properties were reported. Wear tests were performed using a tribometer with ball-on-plate geometry in reciprocating sliding contact under dry condition. It was observed that α/β-SiAlON compositions, doped with Y2O3, have better wear properties in comparison to α-SiAlON and β-Si3N4 samples. Field emission scanning electron microscopy (FESEM) was used to analyse the worn surfaces after wear tests. The results showed that α/β-SiAlON and β-Si3N4 materials have different wear behaviour.