Amorphization/crystallization behaviors of Ti50Al45Si5 multi-component powder treated by mechanical alloying and subsequent heat treatment

In this study, Ti50Al45Si5 multi-component powders are synthesized to investigate their amorphization or crystallization behaviors by mechanical alloying and subsequent heat treatment. The mechanically alloyed Ti50Al45Si5 multi-component powder was ball-milled with different milling time, and the respective crystallographic properties classified. Under the milling time of 5 h, Ti50Al45Si5 powder remained only as a refined single phase of crystallite, and no mechanical alloy behavior occurred. The phase behavior of the 15 h milling showed crystalline/amorphous mixed phases depending on the continuous mechanical alloying, corresponding to the grain refinement and increase of strain energy. At 25 h milling, the mechanically alloyed powder was completely amorphized. To investigate the crystallization behavior of amorphized Ti50Al45Si5 powder, the subsequent heat treatment was conducted at temperature (500 and 850) °C, at which heat flow change was observed during the DTA/DSC analysis. Additionally, the crystallinity was calculated using the Rietveld refinement method by X-ray diffraction for quantitative analysis of the crystalline phases of Ti50Al45Si5 multi-component powder. •Microstructural evolution of mechanically alloyed Ti-Al-Si powder were discussed.•The crystallinity of alloyed powder was determined by a heat treatment temperature.•Quantitative characterization of crystallized phases depend on their MA degree.