IDENTIFICATION ON ZrNbMoGe ALLOY OF 400C-1 HOUR HYDRIDATION TEST FOR CLADDING MATERIALS BY USING DIFFRACTION TECHNIQUE

Synthesis of a new niobium containing zirconium alloy of ZrNbMoGe has been developed in PSTBM-BATAN. In PWR/PHWR reactor, this materials face with liquid coolant i.e. H2O demin that may trig a reaction between hydrogen and containing zirconium. Hydridation tests in argon atmospheer were recently carried out looking for hydrogen effect in material. Hydrogenisation must be avoided due to causing brittle of the material via blistering of Zr-H compound system. Sample with 2%Nb, 0.5%Mo, 0.5%Ge and Zr in balance content has been hydridized by flowing H2 at temperature of 400 oC for an hour. Effects of the test by time-high temperature dependence on the zirconium content were investigated by X-ray diffractometer. The observed peak at 220.95 was mathematically interpolated by orde-2 polynomial regression. Identifying peak was performed by X-ray diffraction technique and then it conformed ’search and match’ by JCPDS tracing. Results show that new phase in 400oC-1 hour hydridation sample was close to crystal structure of –ZrH2. The crystallographic data emphasize that new phase with lattice parameter of a= b= 3.52 Å and c= 4.45 Å (tetragonal) is (201) plane or 221.60. Also, the JCPDS traces another new orthorhombic phase of Nb3H3O9 at angle of 220.91 with lattice parameter of a= 9.183 Å, b= 22.47 Å and c= 4.24 Å conforming to (220) plane. Hypothesized, this is an anti-hydride layer (passivity) that can overcome hydridation process of cladding materials in the reactor.