Calculating the solubility of nitrogen in systems based on iron-chromium-nickel alloys

摘要

In arc welding, the transfer of nitrogen from the gas phase into the weld metal is an undesirable process for many cases. In steels with higher chromium content, nitrogen may play the role of the alloying element.1 In this case, in multicomponent alloys such as steels, it is important to know the limiting content of nitrogen which may be introduced into the metal.2 Experiments were carried out to examine the solubility of nitrogen in iron,3 chromium and manganese and, consequently, the application of the equations presented in Ref. 9 makes it possible to derive calculations for determining the solubility of nitrogen in binary and more complicated systems. Taking into account of the effect of all alloying elements from the data in Ref. 9, for the Fe-C-Si-Ni-Mop Cr the authors obtained the following equations for the partial pressure of nitrogen in the gas phase of pN2= 101 325 Pa and a temperature of 1600 deg C: lg[percent N]=-700/T-0.98-1.75xc/1-xc+lg(1-2xc)-2.0x/1-x+lg(1-2x_(si))-1.264_(nj)+1.7_(Mn)+4.1xc.