FORMATION AND STABILITY OF AMORPHOUS ZN-TI ALLOY BY MECHANICAL ALLOYING

Amorphous Zn-Ti was successfully synthesized for the first time by mec hanical alloying of pure elemental powders of Zn and Ti using a planet ary high energy ball mill. The structure and thermal stability of the alloy were analysed by X-ray diffraction, differential scanning calori metry and high temperature X-ray diffraction. The results indicate tha t the large negative enthalpy of formation for the Zn-Ti system suppli es the driving force for the solid state amorphization reaction. Moreo ver, the Zn atom is also a fast-moving species in the Ti-Zn system and ensures the success of amorphization. The crystallization sequence of the amorphous Zn60Ti40 alloy is that Zn2Ti appears first and then a - / phase forms. The activation energies for the two processes are 1.106 and 1.620 eV respectively.