STRUCTURE OF Ti_(0.9)Zr_(0.1)Mn_(1.5)V_(0.3)Ti_(0.2)D_(2.8)

摘要

The structure of Ti_(0.9)Zr_(0.1)Mn_(1.5)V_(0.3)Ti_(0.2) alloy and its deuteride was studied using methods of X-ray analysis and time-of-flight neutron diffraction (TOFND). The refinement of diffraction profiles was performed using Rietveld method. The refinement of the diffraction profile of the starting alloy showed, that the vanadium atoms are situated in 2(a) sites and titanium atoms in 6(h) sites. That introduction of hydrogen does not change the metal matrix structure and the hydriding is accompanied by isotropic increase of cell volume by 20%. The minimisation of R-factor showed that the best fit is achieved for the model of deuterium location in 3 sites, 24(1), 12(k)_1 and 6(h)|. However, at low temperature approximately 0.11 deuterium atoms relocate from 24(1) to 12(k)_1 position. The analysis of alloy and deuteride structure obtained in this work as well as the reference data allows to draw a conclusion, that the set of sites in hexagonal Laves phase structure which are occupied by deuterium is a stable one and does not depend on temperature or alloy composition.