Hydrogen effects in gamma titanium aluminides

The results of X-ray diffraction studies on Ti-48Al-1V at %(Ti-48-1) are reported. The objective of this study is to investigate the effects of hydrogen on phase changes and hydride formation in these alloys. Hydrogen-induced cracking was found to occur as a result of hydrogen charging. The cracking appears after the hydride phase formation and is observed to be dispersed throughout the material. The hexagonal hydride formed is unlike any previously reported titanium hydride. The hydride exhibits an 8% volume contraction compared to Ti3Al which is made up of a 10% contraction in the a-direction, and a 12.5% expansion in the c-direction.