Study of the formation of the amorphous phase in metallic systems by mechanical alloying

Abstract

At present, there is considerable interest in the formation of amorphous phases in alloy systems, because of the property and processing advantages possible. The advantages of mechanical alloying (MA) for the formation of amorphous phases are a more homogeneous product and good reproducibility. Hence amorphous phase formation through MA in titanium systems was examined and compared with rapid quenching. Because TiNiCu possesses a deep eutectic, favorable diffusivity and heat of mixing, it is prone of the formation of amorphous phases during rapid quenching. The response to similar MA in the systems TiAl, TiMg and commercial purity titanium was also studied since these are not prone to amorphous phase formation in rapid quenching. The results of calorimetry, X-ray and electron diffraction are reported and the mechanism of amorphous phase formation in MA as opposed to that in rapid solidification is discussed.