Mechanochemical synthesis of Ti1−xZrxB2 and Ti1−xHfxB2 solid solutions

Abstract Solid solutions of TiB 2 –ZrB 2 and TiB 2 –HfB 2 were obtained under an inert atmosphere by high-energy ball-milling mixtures of Ti/Zr/B and Ti/Hf/B, respectively. Milling promoted mechanically induced self-sustaining reactions (MSR), and the ignition time was dependent on the initial composition of the mixture. The stoichiometry of Ti 1− x Zr x B 2 and Ti 1− x Hf x B 2 solid solutions was controlled by adjusting the atomic ratio of the reactants. The solid solutions were characterised by X-ray diffraction, transmission electron microscopy, electron diffraction, and energy dispersive X-ray spectroscopy. The results revealed that TiB 2 –ZrB 2 possessed a nanometric microstructure and good chemical homogeneity. However, in the TiB 2 –HfB 2 system, an inhomogeneous solid solution was obtained when a Ti-rich mixture was employed. The solid solutions showed good thermal stability; thus, can be used as raw materials for the development of technological materials for structural applications.