抄録
The structural change in Al75Ni25 powder during MA and MG was studied using SEM, X-ray diffraction and DSC. MA was carried out for the mixture of elemental Al and Ni powders and MG was done for the powder of Al3Ni intermetallic compound prepared by arc melting. In both MA and MG processes, the major end product was found to be disordered AlNi (BCC) which was identified by X-ray diffraction. DSC and x-ray diffraction analysis showed that the disordered AlNi phase transformes directly to Al3Ni intermetallic compound by heating. It was noted that the transformation temperature of disordered AlNi structure to Al3Ni compound in MG powder is higher than that of MA powder. The amount of exothermic heat associated with this transformation in MG powder (1.0kJ/mol) was found to be smaller than that of MA powder (2.5kJ/mol). This difference may arise from the fact that in the case of MG powder Al3Ni compound still partially remains even after heating up to 973K.
