Method for indirect determination of residual impurities by hardness measurement of metal niobium

摘要

The present invention relates to a method for indirectly and simply quantifying oxygen and nitrogen, which are residual impurities of metallic niobium refined at high purity, and discloses a relationship in which the hardness of metal niobium is proportional to the concentrations of oxygen and nitrogen which are residual impurities Using this relationship, it is possible to indirectly determine the concentration of oxygen and nitrogen only by measuring the hardness of metal niobium.;According to the present invention, there is provided a method for manufacturing a niobium-containing niobium powder, comprising the steps of: preparing metal niobium having oxygen and nitrogen concentrations in a range of 1100 ppm or less,;Measuring the hardness of the prepared metal and quantitatively analyzing oxygen and nitrogen to establish the relationship between the hardness of niobium and the concentrations of oxygen and nitrogen which are impurities as described below;;Hv = 3.7 (Co + C_N)^1/2+12.8 (1);(100Co100 ppm, C_N25 ppm);Hv = 5.3 (Co + C_N)^1/2+ 7.2 .. (2);(100 (Co + C_N) 1000 ppm, C_N= Co);This is the indirect measurement of the oxygen and nitrogen concentration of the niobium ingot, indirectly quantifying the impurities, oxygen and nitrogen.