The redistribution of impurities in zirconium at cyclic hydrogenation

The effect of dehydrogenation process temperature on the peculiarities of e lectronegative impurities redistribution in the volume and on the surface o f zirconium have been studied by kinetic method and Auger electron spectros copy. The influence of hydrogenation and dehydrogenation processes on the d ensity of electronic charge on Fe-57 nucleus in Zr2Fe compound have been ex amined by method of nuclear gamma-resonant spectroscopy. The obtained scien tific results by yl resonant spectroscopy method have shown that cubic stru cture of Zr2Fe alloy forms only as a result of carrying out of hydrogenatio n process at temperature of 873 K. It can be explained that at this tempera ture the allotropic transformation (alpha-->beta) of Zirconium matrix occur s at hydrogen concentration of similar to 7 at.% (solid phase transition fr om hexagonal close-packed lattice into body-centered cubic lattice). In thi s case in bcc lattice the volume diffusion of oxygen predominates. The prol onged hydrogenation of zirconium at this temperature promotes the intensive dissolution of oxygen in specimens.