SiC chopped fibers reinforced ZrB2: Effect of the sintering aid

ZrB2 composites containing SiC chopped fibers were hot pressed at 1600-1900 degrees C using different sintering aids. The change of sintering aid strongly affected the densification temperature and the mechanical properties of the composites. Addition of MoSi2 was detrimental to the final microstructure and properties, due to the high temperature needed to reach a full densification. Addition of ZrSi2 decreased the sintering temperature to 1650 degrees C, and the resulting composite containing 20 vol.% fibers reached a toughness of 6.2 M Pa m(0.5). (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.