Alloying evolution and stability of Al 65 Cu 20 Ti 15 during process of amorphisation by high energy ball milling

Abstract

Mechanical alloying of Al₆₅Cu₂₀Ti₁₅ powder blend has been carried out by high energy vibrating ball mill. The process of amorphisation in the mechanically alloyed Al₆₅Cu₂₀Ti₁₅ powder and the stability of the amorphous phase during ball milling were investigated. Almost completely amorphous powder was achieved after 25 h ball milling. Examination of the microstructural constituents using X-ray diffraction and transmission electron microscopy shows that the amorphisation process was controlled by the transformation of both Al based solid solution and intermetallic compounds (Al₂Cu, Cu₉Al₄ and AlCu₂Ti). However, that prolonging the ball milling time to 30 h led to the appearance of Cu₉Al₄, the Al₆₅Cu₂₀Ti₁₅ composite comprising nanocrystalline and amorphous phases could be stable after 50 h ball milling.