Beneficial Effects of AlN as sintering aid on microstructure and mechanical properties of hot pressed ZrB2

The primary effect of the AlN addiiton leads to removal of the boron oxide layer that covers the ZrB2 particles and prevents the achievement of dense sintered bodies. The refinement of grain size and the presence of only refractory secondary phases like Al2O3 and BN has beneficial effects on themechanical properties. Outstanding strength values of 600 and 200 MPa were measured at 20 and 1500°C in ambient air, respectively.