Application of isotope radiography to studies on decarburization of multicomponent low-alloyed steels in sodium

The effect was investigated of the alloying by chromium (1-3%), molybdenum (1-2%), niobium (0-1%), titanium (0-0.25%) and vanadium (0-0.25%) upon the decarburization of low-alloy steels effected by holding them in sodium at temperatures between 500 and 800 deg C for a duration of 5 to 100 h. The investigation was carried out by the experimental design method. The distribution of carbon in depth was studied by means of radiometric analysis with the use of the isotope C14. It was shown that most prone to decarburization are steels with 1-3% Cr and 1% Mo. Carbon content is substantially stabilized by combined alloying with Nb, V and Ti in amounts of up to 0.25% of each element