Jimenez, C.; Garcia-Moreno, F.; Rack, A.; Tucoulou, R.; Klaus, M.; Pfretzschner, B.; Rack, T.; Cloetens, P.; Banhart, J.: Partial decomposition of TiH2 studied in situ by energy-dispersive diffraction and ex situ by diffraction microtomography of hard X-ray synchrotron radiation. Scripta Materialia 66 (2012), p. 757-760
Phase transformations during partial decomposition of TiH2 powder were followed in situ by X-ray diffraction and thermoanalysis. During heating, endothermic H2 release regimes are correlated with the phase transformation sequence, in which the phases a + d + b coexist because a hydrogen concentration gradient forms inside the particles. Cooling from 616 C interrupts degassing close to the eutectoid composition, which suppresses the coexistence of a + d + b. Microtomography indicates that the resulting microstructure comprises d lamellae embedded in an a matrix in the proportions 31:69 (vol.%).