Nitrogen alloying behavior of 316 L stainless steel

The influences of liquid steel temperature,nitrogen partial pressure,and carbon content on the nitrogen solubility in 316 L stainless steel under normal atmosphere and vacuum were studied by the Factsage thermodynamic calculation software and laboratory experiments. Results show that nitrogen solubility increases with decreasing the liquid steel temperature,increasing the nitrogen partial pressure,or decreasing the carbon content. The nitrogen partial pressure is the most important one among the three parameters.The thermodynamic calculation results are in coincidence with the measurement results in different nitrogen blowing processes. Producing 316 LN with the N content of 0.05%- 0.10%(mass fraction) could be conducted during oxygen blowing. Producing 316 LN with the N content of 0.10%- 0.40% should be carried out during charging(the nitrogen partial pressure must be over 30 kPa) and under atmospheric pressure.