The present work focuses on the experimental evaluation of the solubility of nitrogen during the melting process in nickel and binary Ni-Cr alloys under elevated nitrogen partial pressure at 1550 deg C. In order to estimate the attainable nitrogen concentrations, the solubility of nitrogen in dependence of melt temperature and nitrogen partial pressure has been calculated by using Thermo-Calc.Thermo-Calc supported predictions of the achievable nitrogen contents referring to the investigated alloys show good agreement with the experimental data only up to nitrogen partial pressures of 0.1 MPa.The applicability of Sievert's law has been examined for nitrogen partial pressures up to 6 MPa and Ni-Cr alloys with chromium mass contents of 15, 20 30, 40 and 50 percent. A deviation from Sievert's law was observed for the alloys with chromium mass contents higher than 20 percent and a nitrogen partial pressure above 0.1 MPa.The effect of chromium and the nitrogen partial pressure on the solubility of nitrogen is described in terms of the Wagner's first and second order interaction parameters.
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