In situ synchrotron radiation to understand the pathways for the scavenging of oxygen in commercially pure Ti and Ti-6Al-4V by yttrium hydride

In situ synchrotron radiation revealed how the scavenging of oxygen by yttrium hydride (YH2) occurred in powder metallurgy commercially pure Ti (CP-Ti) and Ti-6Al-4V. YH2 decomposes at >900 degrees C in CP-Ti and at >1100 degrees C in Ti-6Al-4V. Elemental Y coexists with Y2O3 in both CP-Ti and Ti-6Al-4V up to 1300 degrees C. Ex situ analytical means further confirmed that the scavenging product is Y2O3. Together with available diffusion data, mechanisms are proposed to understand the decomposition of YH2 and the scavenging of oxygen in CP-Ti and Ti-6Al-4V. (c) 2012 Acta Materialia Inc.