Abstract:Nanocrystalline Ti-Al composite powders with composition of Ti-47Al (at%) and Ti-45Al-2Cr-2Nb-1B-0.5Ta (at%) were prepared by double-steps balll milling (ball milling+heat treatment+ball milling) using elemental powders. The as prepared and heat treated powders were analyzed and characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), differential thermal analysis (DTA) and particle-size distribution analyzer. The results demonstrated that high-quality composite powders with low contaminant, uniform size distribution and homogeneous elements dispersion could be obtained by the double-steps ball milling. The composite Ti/Al powders prepared by primary ball milling (6 h) were uniform. Ti3Al、Ti、Al3Ti and TiAl phases were found after heat treatment (700 ℃, 2 h) while Al phase disappeared. The fined grain size and particle size were further reduced by subsequent ball milling.