Amorphization of Mixed Ni and Zr Powders with Ni-rich Compositions by Mechanical Alloying

Abstract

Pure crystalline powders of Ni and Zr were mechanically alloyed by high-ener-gy ball milling in an argon atmosphere and amorphous Ni_xZr_100-x alloy powders (X=75, 80, 85 and 90) were synthesized. The alloying and amorphization process was examined by X-ray diffractometry and differential scanning calorimetry.
The X-ray scattering vector, K_p, of the broad amorphous maximum for the mechanically alloyed Ni-Zr amorphous powders are identical with those of liquid quenched amorphous alloys of the same compositions, except for x=90. The crystallization temperature and the crystallization enthalpy of the Ni-Zr amorphous powders as a function of Ni composition are investigated.