SYNTHESIS AND ELECTRON-MICROSCOPY OF THE STRUCTURE OF ZETA-HF4N3

High temperature synthesis of zeta -Hf//4N//3 from powdered hafnium metal and hafnium mononitride was carried out at the melting temperature of the metallic component. Detailed X-ray diffraction, metallography and transmission electron microscopy analyses were used to establish the structure of the zeta phase. The mechanism of zeta phase formation based on filling the octahedral interstices in left brace 111 right brace planes was refined. Orientation relationships for matching zeta -Hf//4N//3 with the non-stoichiometric fcc hafnium nitride HfN//1// minus //x were established.