Stainless Steel In Sulfuric Solution Research Articles

The Growth Mechanism of the Coloured Passive Film Formed on 304 Stainless Steel in Sulfuric Solution without Cr6+ ion by using A.V. Passivation

SUMMARYA thick passive film showing interference colours has been obtained on 304 stainless steel in sulfuric acid solution without Cr6+ ions by applying alternating square wave polarization. An investigation of the chemical composition and the distribution of valence states in the profile of the film has been carried out by using XPS. A mechanism for the colouring process is proposed