Effects of additive Nb and sintering temperature on the properties of ZrN powder materials

The Nb-ZrN powder materials were prepared by hot pressing sintering, adding Nb powders as the additive in ZrN matrix. Effects of additive Nb and sintering temperature on the sintering and mechanical properties of ZrN powder materials were researched. The results show that, the increase of sintering temperature benefits the material densification, a densification rate peak is present in Nb-ZrN1480 powder materials, and two other small rate peak appear in other Nb-ZrN powder materials. The relative density of Nb-ZrN1680 powders after sintering can achieve as high as 98.6%. The diffraction peak of ZrO₂ is found in X-ray diffraction spectra of all Nb-ZrN powders, the additive Nb dissolves into the ZrN matrix in sintering stage. After adding Nb as the additive, the ZrN lattice constant reduces and then remains stable with the increase of sintering temperature. Pure ZrN shows the intergranular fracture, the Nb-ZrN powder materials exhibit the transgranular fracture, and the number of pore is decreased obviously.