Hot Isostatic Pressing of Composite Powder in the System ZrO₂-WSi₂ Part1: Microstructure and Mechanical Properties of ZrO₂ (2mol% Y₂O₃)-Reinforced WSi₂ Composites

Abstract

Dense sintered composites of ZrO₂ (2mol% Y₂O₃) and WSi₂ have been fabricated by hot isostatic pressing for 2 h at 1500°C under 196 MPa. They contain a small amount of W₅Si₃; during sintering, WSi₂ decomposes into W₅Si₃ and amorphous Si. The ZrO₂ particles in the composites consist of only t-ZrO₂ Microstructures and mechanical properties are examined, in connection with increased Zr0₂ content. The fracture toughness and bending strength of the composite with 40 mol% ZrO₂ addition are 7.1 MPa·m^1/2 and 1010 MPa, respectively.