NONOX World

Austenitic stainless and acid-resistant steels belong in the category of active corrosion protection thanks to their alloying materials. Even so, they can corrode in practice. Rust contamination, surface, local, contact, stress and mechanical corrosion, and how to guard against each.

Iron is an important element of living organisms and one of our most heavily used industrial materials, especially its alloy with carbon: steel. From classification and the effect of carbon to the alloying elements behind corrosion-resistant and acid-resistant grades, here is what shapes the properties of steels.

By definition, corrosion is the destruction of metals by an electrochemical process. In a dry medium iron does not rust, yet corrosion causes an estimated HUF 50 billion of damage a year in Hungary. Local cells, protective coatings, galvanising and cathodic protection explained.

Protective coatings only protect while they remain intact. The other fundamental method of protection against corrosion is alloying, thanks to which stainless and acid-resistant steels came into being. From iron-carbon alloys to the welding and standardisation of A2 and A4 grades.

Extract from standard DIN EN ISO 3506. Steel groups and strength classes are designated by a sequence of letters and numbers consisting of 4 characters. The letters denote the general classification of the steel groups: A = austenitic steels, C = martensitic steels, F = ferritic steels.