Synthesis and analysis of ZrB2-based composites

Composites with different compositions were prepared from ZrB2 and Mo. It was found that there is an optimum composition for obtaining the highest relative density at 15 wt.% of molybdenum. Based on the results of x-ray diffraction analysis, energy dispersive spectrum analysis and elemental mapping, it was concluded that the composites contained ZrB2, MoB, and ZrC due to the reactions between ZrB2, Mo and some C (presents as an impurity). The effects of composition and firing temperature on the firing of ZrB2-Cu were studied. The relative densities of green bodies and fired composites increased with increasing amount of copper. For the composites containing 25 vol.% copper, the relative densities increased first with increasing firing temperature, and then decreased at higher firing temperature due to the loss of boron during firing.