Numerical and experimental research of the influence of hydrogen on the fracture toughness of zirconium – 2.5% niobium alloy

Abstract

The aim of work was the experimental investiga-tion and numerical modelling using finite element method of influence of hydrogen to the fracture toughness of Zr-2.5 Nb alloy of a pipe of the fuel channel with ТМT-2 re-actor RBMK-1500. Calculation of characteristics of frac-ture toughness was made with use of experimentally de-termined mechanical properties of zirconium alloy contain-ing hydrogen up to 137 ppm. Comparison of the received results of calculation with experimental data has shown, that the calculated intensity factors KQ and KC*, and also their dependences on concentration of hydrogen are be-tween experimental points. Including the spread of ex-perimental results, their deviation from calculated data does not exceed 6%. It was determined, that the increase in of hydrogen concentration up to 137 ppm at 20°С de-creases the value of intensity factor KQ by 13% and KC* by 24%.