Effect of chromium and nickel on nitrogen absorption of arc-melted iron

Fe-Cr and Fe-Ni alloys were melted by tungsten arc-melting under argon-nitrogen gas mixture atmosphere with various melting conditions in order to study effects of chromium and nickel on the nitrogen absorption of arc-melted iron. In Fe-Cr alloys with chromium more than 8%, the nitrogen content decreases with an increasing arc current. In Fe-Cr alloys with chromium less than 5.6% and Fe-Ni alloys, the nitrogen content increases slightly with arc current. In all alloys, the nitrogen content increases with arc-melting time and then reaches the saturated value which increases with the nitrogen partial pressure of atmosphere, but does not obey Sieverts' law. The nitrogen content of arc-melted iron increases largely with the chromium content, and decreases slightly with an increasing nickel content.