Peculiarities of ball-milling induced crystalline–amorphous transformation in Cu–Zr–Al–Ni–Ti alloys

• CuZrAl(Ni,Ti) alloys were ball-milled.
• Structure transformation induced by ball-milling was investigated.
• Amorphous volume fraction was defined as a function of milling time.
• The effect of alloying elements was revealed and discussed.

An amorphization process in (Cu49Zr45−xAl6+x)100−y−zNiyTiz (x = 1, y, z = 0; 5; 10) induced by ball-milling is reported in the present work. The aim was investigation of the effect of Ni and Ti addition to Cu49Zr45Al6 and Cu49Zr44Al7 based alloys as well as type of initial phases on the amorphization processes. Also the milling time sufficient for obtaining fully amorphous state was determined. The entire milling process lasted 25 h. Drastic structural changes were observed in each alloy after first 5 h of milling. In most cases, after 15 h of milling the powders had fully amorphous structure according to XRD except for those ones, where TEM revealed a few nanosized crystalline particles in the amorphous matrix. In (Cu49Zr45Al6)80Ni10Ti10 alloy the amorphization process took place after 12 h of milling and the amorphous state was stable up to 25 h of milling. In the case of (Cu49Zr44Al7)80Ni10Ti10 alloy the powders have fully amorphous structure between 12 h and 15 h of milling.