Oxidation resistance of ZrB2 and ZrB2-SiC ultrafine powders synthesized by a combined sol-gel and boro/carbothermal reduction method

ZrB2 and ZrB2-SiC powders were prepared by a combined sol-gel and boro/carbothermal reduction method, and their oxidation kinetics was studied by using a non-isothermal thermogravimetric technique. The results showed that the Mample power law (n=1) was the most probable mechanism function, and the incorporation of SiC into ZrB2 greatly enhance the latter's oxidation resistance. The oxidation activation energy values of phase pure ZrB2 and ZrB2-SiC powders were respectively 249 and 308 kJ/mol.