Steel is alloy of iron with carbon, at carbon content no more than 2.14%. In such quantities carbon gives to iron the hardness and durability, saving from the main shortcoming - plasticity.
What stainless steels happen
If steel is capable to resist corrosion at long contacts with hostile environment or humidity, an atmospheric precipitation, it is called corrosion-proof. Properties of stainless steel directly depend on a look and amount of additives, that is on its chemical composition. Stainless steel in itself – very beautiful material having the increased wear resistance.
The basic alloying element (that is the additive giving to steel resistance to corrosion) – chrome. From what amount of this substance contains alloy, its resilience to corrosion, especially in hostile environment directly depends. Any grade of stainless steel contains at least 10.5% of chrome (on weight).
If chrome content in alloy is more than 17%, such steel is not exposed to corrosion even under the influence of strong acids.
Except chrome, as the alloying additives use a number of elements, for example manganese, nickel, titanium, cobalt, molybdenum, vanadium, tungsten, silicon, niobium, etc. Nickel is especially often applied. Let's say if on some household subject from stainless steel there is designation 18/10, it indicates that alloy of which the subject is made contains 18 weight percent of chrome and 10 weight percent of nickel.
Each of the alloying additives is responsible for something. For example, tungsten gives to steel refractoriness, molybdenum – wear resistance, and manganese – hardness.
The resistance to corrosion acquired by steel after addition of the alloying components is explained, mainly, by the fact that on the surface of the alloy containing chrome the thinnest film of oxides of this element is formed. It also protects steel from influence of hostile environment. Stainless steel finds exclusively broad application in various industries and in life. Manufacture of it cases of chemical reactors, the shovels of turbines cutting, a measuring and surgical instrument, parts of weapon, valves of hydraulic presses, springs, tableware, etc.
As it is possible to define the chemical composition of stainless steel
It is possible to learn exact structure of steel only in laboratory, having carried out the spectral analysis. In house conditions of it the expert will not manage to make even, devices are for this purpose necessary. It is possible to make idea of approximate content of the main alloying additives on marking of a product.