Fabrication of TiH2 Powders from Titanium Tuning Chip by Mechanical Milling
In present work, manufacturing technologies of titanium hydride powder were studied for recycling of titanium tuning chip and for this, attrition ball milling was carried out under H2 pressure of 0.5 MPa. Ti chips were completely transformed into TiH2 within several hundred seconds that is very short time comparing to that in the previous report. Dehydrogenation process TiH2 powders is consist of two reactions: one is reaction of TiH2 to TiHx and the other decomposition of TiHx to Ti and H2. The former reaction shows relatively low activation energy ranged from about 100 KJ/mol to 250 KJ/mol and it is suggested that the reaction is caused by introduction of defects due to milling. In case of TiH2 powders that hardly contains defects, decomposition of TiH2 to Ti and H2 occurs directly without the reaction of TiH2 to TiHx and activation energy is very large as much as 929 KJ/mol.
Duk Yong Yoon, Suk-Joong L. Kang, Kwang Yong Eun and Yong-Seog Kim
J. M. Jang et al., "Fabrication of TiH2 Powders from Titanium Tuning Chip by Mechanical Milling ", Materials Science Forum, Vols. 534-536, pp. 185-188, 2007