W-ZrC composites prepared by reactive melt infiltration of Zr2Cu alloy into partially carburized W preforms

Abstract

W-ZrC composites without residual WC have been prepared for the first time by reactive infiltration at 1300°C for 1h in vacuum using a molten Zr2Cu alloy and a newly designed partially-carburized W powder as raw materials. The as-synthesized composites consist of two major phases of W and ZrC, in which the content of W is 65vol%. The reaction time needed to produce a fully densified W-ZrC bulk ceramic is distinctly shortened by this means, as contrasted with conventional WC/W or WC preforms. The microstructural evolution during reactive melt infiltration is investigated to obtain a better understanding of reaction mechanisms and mechanical properties of the W-ZrC composites derived by infiltrating Zr2Cu alloy into partially carburized W preforms. The flexural strength, Young's modulus and fracture toughness for the W-ZrC composite are 554MPa, 339GPa and 9.7MPa·m1/2, respectively.