Nitrogen and oxygen concentration in zirconium alloy with 2,5 % niobium after arc welding in controlled atmosphere

Results on investigation of kinetics and mechanism of nitrogen and oxygen interaction with Zr alloy with 2.5% niobium are presented for the process of arc welding at partial pressure of nitrogen and oxygen in helium within the 10-5000 Pa pressure range. It is established that equilibrium gas concentration is achieved after 16-20 s of melting. Nitrogen absorption is governed by the basic Siverts law and oxygen - by the Henry law. Increase of welding rate from 0.28 up to 1.68 cm/s decreases a degree of weld metal saturation with nitrogen and oxygen. Equations allowing to calculate concentrations of nitrogen and oxygen absorbed by melted weldpool metal are suggested