Structural and phase transformations and hardness of ceramics produced by high-temperature zirconium nitriding

Abstract

Resistive heating of zirconium in a gaseous nitrogen atmosphere yields ceramics based on zirconium nitride with a heterophase structure. X-ray powder diffraction analysis determined the compositions of phases of the synthesized ceramics. The surface of the material consists of zirconium nitride close in composition to ZrN. In the bulk of the materials, in shallower layers, a nitrogen-deficient nitride phase forms, and in deeper layers, a phase of solid solution of nitrogen in zirconium does. The hardness of ceramics based on heterostructures of the type Zr_{solid solution}/ZrN_1–x/ZrN was studied. Changes in the structure and phase composition during high-temperature nitriding of zirconium foil at 1500 and 2400°C were described.