FORMATION OF AMORPHOUS ALUMINUM TANTALUM NITRIDE POWDERS BY MECHANICAL ALLOYING

Aluminum tantalum nitride amorphous alloy powders have been synthesized by a high energy ball mill under purified nitrogen gas (N2) flow at room temperature. The alloy powders were characterized by means of transmission electron microscopy, differential thermal analysis, and chemical analysis. An amorphous phase containing 18 at. % N2 was obtained after 65 ks of the milling time. At the final stage of milling (72 ks) the crystallization temperature, T(x), and enthalpy change of crystallization, DELTA-H(x), are 1115 K and - 95 kJ mol-1, respectively.