WU Nianqiang;LI Zhizhang(Zhe jiang University;Hangzhou 310027). SOLID-STATE REACTION AND PHASE TRANSFORMATION OF Al_(57.1)C_(42.9) POWDER MIXTURE DURING MECHANICAL ALLOYING. Acta Metall Sin, 1997, 33(11): 1155-1160.
Abstract Mechanical alloying of the Al57.1C42.9 powder mixture has been performed in a high-energy ball mill.The structural evolution has been characterized by X-ray diffraction, transmission electron microscopy and infrared spectrometry. Carbide Al4C3 intermediate product is firstly formed. The reaction is controlled by interdiffusion of elements. Further milling leads to transformation of Al4C3 to amorphous phase.Destabilization of Al4C3 is assumed to arise from the fact that defects and chemical disordering raise the free energy of crystal beyond that of the amorphous phase.