Various experimental techniques have been used to investigate the effect of mechanical milling on the structural stability of rapidly solidified aluminum-basedmetallic glasses. Using transmission electron microscopy (TEM) and X-ray diffraction methods, the formation of nanocrystalline Al particles in some ball-milledAl-rich metallic glasses (such as Al//90Fe//5Gd//5 and Al//90Fe//5Ce//5) is clearly observed. For other composiions with lower Al concentration such as Al//85i//5Y//10, no such phase transformation can be detected by TEM or X-ray. However,differential scanning calorimetry (DSC) measurements show that the crystallization peaks of the ball-milled Al//85Ni//5Y//10 metallic glass shifted to hiher temperatures, while the crystallization enthalpy associated with the first exothermic peak decreased to a lower vlaue, revealing that certain structural changes have taken place as a result of mechanical deformation. The compositional dependence of the structural stability of Al-based metallic glasses against mechanical deformation suggests that the nanocrystal formation induced by a deformation process is different from that caused by a thermal process. The large plastic strain induced atomic displacements and the enhancement of atomic mobility during thedeformation process, are the possible mechanissm of mechanical deformation-induced crystallization. Our results demonstrate a new way of obtaining nanophase glassy composite alloy powders which are suitable for engineering applications upon
He, Y. Shiflet, G. J.
