Influence of hydrogenation on characteristics of resistance to fracture of welded joints of zirconium alloys

For a characteristic of the failure resistance of welded joints the deformation criterion is used, i.e. the opening of the fissure at its top, which is determined in bending. It has been established that hydrogen absorption reduces the failure resistance of all the zones of welded joints of the zirconium alloy with 25% niobium at a temeprature of 20 deg C. With an increase in temperature the failure resistance increases, and at a temperature of 250-300 deg C hydrogen absorption practically does not affect the characteristics of the failure resistance. The relationship between the applied stress, the fissure length and its opening for a cylindrical shell has been obtained. Hydrogen absorption greatly reduces the critical lengths of fissures at equal stress levels, although the values of critical fissure lengths are sufficiently high even at low hydrogen absorption (0.05%)