In situ synthesis of ZrB2-MoSi2 platelet composites: Reactive hot pressing process, microstructure and mechanical properties

Using elemental Zr, B, lo and Si as raw materials, partially textured ZrB2-MoSi2 composites with in situ platelet ZrB2 grains were fabricated by reactive hot pressing. Synthesized by a combustion reaction, the in situ formed ZrB2 phase had unique characteristics to grow up to platelet grains, on the surroundings of Mo-Si-B ternary liquid phase at high temperature. Mechanical properties were dependent on grain size and aspect ratio of the ZrB2 platelets. The rotation and realignment of the platelet ZrB2 grains under hot pressing led to a partially textured microstructure, which showed anisotropic mechanical properties on different directions of the as-sintered samples. A roadmap of the reaction process, microstructure evolution and texture formation was given to describe the preparation of partially textured ZrB2-MoSi2 composites by reactive hot pressing. (C) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.