UNI 3177-1952 Procedures for chemical analysis of metallic materials. Determination of vanadium content of steel. Reduction method with iron sulphate and titration with potassium permanganate.
Vanadium is reduced in cold acid solution to the tetravalent state with excess ferrous ammonium sulphate. The excess of ferrous ammonium sulphate is oxidised with ammonium persulphate which, in the conditions described, does not react with tetravalent vanadium, with divalent manganese, with trivalent chromium and with potassium permanganate which is finally used to titrate the vanadium, reoxidising it to the solution state and reactive. Process for chrome-vanadium steels with chromium contents lower than 5 percent process for chrome-tungsten-vanadium steels. Cupferron process for steels with high chromium and nickel content. Sodium bicarbonate process for steels and cast irons with vanadium content less than 0.1 percent. Cupferron process for steels and cast irons with vanadium contents lower than 0.1 percent. Process for steels with high carbon and chromium content. Calculation
UNI 3177-1952 history
1952UNI 3177-1952 Procedures for chemical analysis of metallic materials. Determination of vanadium content of steel. Reduction method with iron sulphate and titration with potassium permanganate.