ORDERING OF CHEMICALLY DISORDERED NI3AL AND NI3GE PREPARED BY MECHANICAL ALLOYING

The process of formation of chemically disordered nanocrystalline f.c.c. Ni3Al and f.c.c. Ni3Ge by mechanical alloying (MA) of a mixture of elemental powders was investigated by X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The ordering behavior of these f.c.c. compounds was investigated by both DSC and XRD, and the ordering enthalpy, the ordering temperature and the activation energy of ordering were determined. The differences in ordering behavior between Ni3Al and Ni3Ge were discussed.