Influence of WC particles on the microstructural and mechanical properties of 3mol% Y₂O₃ stabilized ZrO₂ matrix composites produced by hot pressing

Yttria stabilized polycrystalline tetragonal zirconia (Y-TZP)-tungsten carbide (WC) composites were fabricated by hot pressing. Yttria (Y₂O₃) stabilizer content was kept at 3mol% to ensure the phase structure of the Y-TZP composites to be tetragonal. To increase the moderate hardness of the 3mol% Y₂O₃ added TZP structure, hard WC particles were added with various proportions up to 40vol%. The TZP/WC composites were sintered at different sintering temperatures between 1450 and 1550°C.The mechanical and microstructural properties of the resulting composites as well as the phase compositions were investigated. Reciprocating pin-on-disk tests were carried out to determine the wear behavior of the Y-TZP/WC composites. Using bi-modal WC reinforcement, the performance of the composite against wear was improved. Using dry wear sliding conditions under 55N normal load and 45km sliding distance, the worn volume of the 75vol% nanosized - WC distributed 3Y-TZP/40WC composite was about 0.003mm³.