SUPERCHARGING OF ZIRCALOY-4

During service, nuclear components of low thickness made of Zr alloys may reach hydrogen contents above the terminal solid solubility, being the excess hydrogen precipitated as uniformly distributed particles ( supercharging). This phenomenon can produce alloy embrittlement. To ev aluate the behaviour of the hydrided material, it is necessary to obta in similar hydride distributions in the laboratory. In the present wor k, two hydriding methods have been tested: (1) corrosion in LIOH solut ion; (2) gas phase charging on samples coated with Cu. The latter requ ires a relatively short hydriding time, does not affect the microstruc ture and allows a simultaneous measurement of hydrogen content. (C) 19 97 Elsevier Science B.V.