Synthesis of Amorphous Ti50Al50 by Mechanical Alloying
Blended elemental powders with the nominal compositions (at%) of Ti50Al50, was mechanically alloyed in a planetary ball milling system for up to 100h, an amorphous Ti50Al50 phase was obtained in the process. The amorphization process as a function of time of milling was monitored by scanning electron microscope, X-ray diffraction and transmission electron microscope. It is shown that, as first, Al atoms diffuse into the host lattice of hexagonal Ti; subsequently, the milling accumulates a critical density of disorder that causes the Ti (Al) crystalline phase to collapse into an amorphous phase, it is suggested the grain size condition for formation of amorphous phase is 12nm. On the basis of thermodynamic models, the formation of the amorphous phase is discussed.
Chunliang Zhang and Liangchi Zhang
J. H. Zhang et al., "Synthesis of Amorphous Ti50Al50 by Mechanical Alloying", Key Engineering Materials, Vols. 531-532, pp. 490-495, 2013