Mechanosynthesis of nanocrystalline ZrB₂-based powders by mechanically induced self-sustaining reaction method

Abstract

Preparation of nanocrystalline ZrB2–based powder by aluminothermic and magnesiothermic reductions in M/ZrO2/B2O3 (M = Al or Mg) systems was investigated. In this research, high energy ball milling was employed to persuade necessary conditions for the occurrence of a mechanically induced self-sustaining reaction (MSR). The course of MSR reactions were recorded by a noticeable pressure rise in the system during milling. Ignition times for ZrB2 formation by aluminothermic and magnesiothermic reductions were found to be 13 and 6 min, respectively. Zirconium diboride formation mechanism in both systems was explained through the analysis of the relevant sub-reactions.