When speaking about the personal qualities of a person, use the epithet of "steel", mean indomitable character, strong will and acumen, which is not so easy to win.Steel invented to do sturdy and reliable mechanisms, tools and weapons.Now without this metal is indispensable.
What is it - the steel and how it differs from the iron?The main difference in impurities, chief among them - carbon.In order to impart special properties of this metal in the alloy is added to the other components.
The same grade of steel in various countries designated in different ways.Unfortunately, in such an important matter to a common denominator has not yet come.
throughout the former Soviet Union, with the exception of the Baltic states, used alphanumeric codes in accordance with state standards in force earlier.Such a definition of the brand have become very convenient and understandable, the figure indicates the percentage of impurities, and the letter - a chemical element.
Steels simple in structure of which there are only iron and carbon, called structural.They represent simple, Article 2, for example.This means that the carbon therein 0.2%.
quality unalloyed steel has a similar encoding, but the percentage of carbon is reflected by two digital signs, such St.08.
If the metal is used for the production of vessels, which will be working under high pressure, the specific requirements for it.As in the case of high-quality structural steel, the percentage of double-digit, but in the end it added the letter "K" (example - St.12K).
More complex metallurgical composition divided into groups - tools, construction, stainless steel and so on.Each of them has its own characteristics labeling, but common is the letter of alloying elements such as nickel (H), chromium (X), copper (H), Tungsten (V), manganese (T), molybdenum (M), silicon (C), cobalt (K).
deoxidation method is also reflected in the coding steels.Thus, the "quiet" is indicated by the letters SP, "semi-killed" - the SS and "boiling" - KP.
alloyed steels have a longer designation that includes both letters and numbers.It should be remembered that when the content of impurities of less than a half percent figure is not placed.Thus, the code 10 X2 M-W would mean that the steel contains 0.1% carbon, 0.2% chromium and less than 1.5% molybdenum.There is also the letter "W", she says of reduced phosphate content.If instead it was "A", then it came to sulfur.These marks indicate the additional quality characteristics.
Structural steel casting is designated at the end of the letter "L".
for building structures required metal with a low yield strength, it reflects the letter "C" standing in front.Letter standing behind, shows the advanced properties (T - about thermostrengthening, K - for corrosion resistance).
Determination of steels suitable for the production of instruments made by the letter "Y", which is placed after the double-digit percentage of carbon, such as U8.
There are also stainless steel.Brands, like 08X18H10T look like a complicated code, but in reality is the same principle as for the alloy structural alloys.It does not apply to special cases where the letters are assigned in honor of combines, for the first time to smelt the metal with special properties.
