Hydride Reorientation and Redistribution Under Non-Uniform Stress

摘要

The work seeks to quantify hydrides reorientation andredistribution in a duplex nuclear fuel cladding under nonuniformstress. To this end, the tube segments underwent athermo-mechanical treatment following hydrogenation,and then were measured at the PSI spallation neutronsource with the Neutron Microscope setup. The results arediscussed with respect to the hoop stress field calculatedby finite element modeling.Radial hydrides were found in the areas submitted totensile hoop stress. The hydrogen quantification of neutronimaging revealed the interactive effect of the applied stressand the material heterogeneity on hydrides distribution,considering the liner always sinking hydrogen anddepleting the nearby substrate. With the presence of thetensile hoop stress, the hydrogen concentration wasincreased both in the liner and in the substrate nearby theinterface, due to the presence of radial hydrides, while theaccumulation at the interface was reduced. In contrast, thecompressive hoop stress enhanced the interfaceaccumulation and reduced the concentration in the linerinterior. The result demonstrates that the hydridesreorientation can promote the local redistribution ofhydrogen in response to stress.