Solubility of Nitrogen in Liquid Iron and Effect of Carbon, Silicon and Manganese on the Solubility

Solubility of nitrogen in liquid iron and iron alloys-I

Abstract

The solubilities of nitrogen in liquid iron and liquid Fe-C, Fe-Si and Fe-Mn alloys were measured at 1500-1700°C.
The results on liquid iron confirmed that Sievert's law was followed in the range 95 to 760mmHg pressure.
The results obtained were as follows:
(1) The solubility of nitrogen in liquid pure iron was expressed as follows:
%N=1·2×10^-5×T+0·0171
(2) The effect of carbon, silicon and manganese on the activity coefficient of nitrogen in liquid iron alloys was calculated by the following relation:
logfN=logC⁰_N-logC_N
(3) The effect of alloying elements on the activity coefficient of nitrogen in liquid iron was summarized as below:
logf ^(C) _N=+0·135·%C C<4%
logf ^(Si) _N=+0·048·%Si Si<4%
logf ^(Mn) _N=-0·020%·%Mn Mn<4%
1500-1700°C