Journal of the Southern African Institute of Mining and Metallurgy
On-line version ISSN 2411-9717
MAHLATJI, M.L. et al. Formation of amorphous Ti-50 at.% Pt by solid-state reactions during mechanical alloying. J. S. Afr. Inst. Min. Metall. [online]. 2014, vol.114, n.2, pp. 167-172. ISSN 2411-9717.
Mechanical alloying of an equiatomic mixture of crystalline Ti and Pt elemental powders in a high-energy ball mill formed an amorphous alloy by solid-state reactions. Mechanical alloying was carried out in an argon atmosphere at a rotation speed of 1200 r/min and a 20:1 ball-to-powder weight ratio, for time intervals of 4 to 40 hours. At an intermediate stage of mechanical alloying, scanning electron microscopy showed the formation of characteristic layered structures of inhomogeneous composition within the powder particles. X-ray diffraction analysis showed the gradual disappearance of crystalline Bragg peaks and the emergence of broad amorphous maxima as milling progressed. The amorphization process was completed after 8-12 hours. The amorphous state of the product indicated that temperatures during processing did not exceed the crystallization temperature of the alloy.
Keywords : TiPt alloy; mechanical alloying; amorphization; solid-state reactions.