Question

Is it true that stainless steel really stainless in construction purpose?

Answer

Stainless steel refers to alloy steels with more than 10.5 percent of chromium and contains some groups like austenitic, ferritic, martensitic etc. Austenitic stainless steel is usually used in structural applications since of its high corrosion resistance. Austenitic and ferritic types of stainless steel cover about 95 percent of stainless steel functions. Stainless steel is not stainless though it is anti -corrosion under a wide range of situations.

An inactive layer of chromium oxide is created on stainless steels surface that renders it corrosion resistant. This chromium oxide layer acts as a hard physical barrier to guard beside corrosion and creates it chemically stable. Besides, as this layer is damaged, it is able to perform self repairing anywhere there is an enough supply of oxygen. Yet, stainless steel will silent corrode by pitting in marine environment where chloride bother happens.

So, an appropriate grade and type of stainless steel has to be selected in polluted and marine environment to reduce trouble of corrosion.