Stainless steels are a group of high alloy steels, characterized by high resistance to atmospheric, water and earth corrosion. 
The main alloying addition in stainless steels is chromium, which(depending on the grade)occurs in an amount from 12% to 19%.
Greater resistance to corrosion of steel can be obtained by the following:
- Increasing its electrochemical potential by the introduction of metal having a higher electrochemical potential
(In this case chromium at least 13-14%),
- creating of oxides on the steel surface (passivation of steel), by the addition of chromium, aluminum, silicon.
Stainless steel, containing from 13% to 14% is resistant to corrosion in an oxidizing environment (cold dilute nitric acid HNO 3),
it is not resistant to corrosion in reducing environments (Sulfuric acid H 2 SO 4, hydrochloric acid, HCl). The higher the carbon
content the less resistant to corrosion the steel is especially if carbon is occurs as carbides. Steel containing up to 0.15% of
carbon has a ferrite structure in the whole range of temperatures, steel with carbon content of 0,15-0,35% after heating to
the temperature above 950 °C and cooling will get the half-ferrite structure (ferrite and martensite) steels containing more
than 0.35% after cooling have martensitic structure.

The symbol of the grade is modeled on the steels according to older GOST norms older, consists of letters identifying
the alloying elements:

H - Chrome
N - Nickel
J - Aluminum
M - Molybdenum
T - Titanium

and the numbers appearing after the letters that inform about the average content of a certain element in%.
In cases where grades differ only in carbon content, for their distinction at the beginning of the marking before
the letter H a number is given, eg. H17N2 means steel with an average content of chromium 17% and of nickel 2%.
2H13 - chrome steel 
4H13 - chrome steel
H17 - high chrome steel
2H17N2 - stainless chromium nickel
3H17M - chrome molybdenum
H18 - stainless chrome steel






Out of stainless steel grades we offer - metal plates,forged bars, rolled bars, forgings, stainless steel pipes 
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