Characterizations of mechanically alloyed Ti-Zr-Cu-Ni powders

Influences of Zr and Ti contents on amorphization of Ti-Zr-Cu-Ni alloy induced by mechanical alloying are studied. It is found that by increasing Zr content, the 100 h-milled Cu58-xZrxTi34Ni8 (at %) alloys change from a single fee solid solution (x = 0) to a partially amorphous state (x = 11) and finally to almost a single amorphous phase (x greater than or equal to 31). By changing Ti content, partial amorphization is confirmed to occur in the Cu47Zr11Ni42-xTix (at.%) alloy with x greater than or equal to 22. Influences of Zr and Ti contents on the thermal stability of the as-milled Cu58-xZrxTi34Ni8 and Cu47Zr11Ni42-xTix alloys are investigated by means of a differential scanning calorimeter and X-ray diffraction. Oxidation of zirconium in the above as-milled alloys upon heating is discussed. (C) 1998 Elsevier Science S.A. All rights reserved.