The numbers after each letter represent an example of an appropriate element, but the content of alloying elements less than 1.5% figure after the corresponding letter is not raised. Qualitative Additional indicators decreased content of impurities such as sulfur and phosphate are denoted by the letter – A or H, at the end of designations, such as (12 X NZA, 18HG-W), etc. The structural steel foundry, according to GOST 977-88, referred to as quality and alloy, but at the end of the name of the letter L. Steel construction, according to GOST 27772-88, denoted by the letter C and the numbers corresponding to the minimum yield strength of steel. Advanced use notation: T – heat-rolling, K – high corrosion resistance (eg, C 345 T C 390 K, etc.). Similarly, the letter D indicate higher content of copper.
Bearing steel, according to GOST 801-78, also designated as doped, but with the letter W at the end of the name. It should be noted that the ESR steel letter W is denoted by dashes (eg ShKh 15 SHH4-III). Unalloyed steel tools, according to GOST 1435-90 is divided into quality, denoted by the letter Y and figures indicating the average carbon content (for example, U7, U8, U10) and high-quality, designated with an A at the end of name (for example, U8A) or an additional letter T, indicating a further increase in manganese content (eg, U8GA). Steel alloyed tool, according to GOST 5950-73, are also designated as structural alloy (eg 4H2V5MF, etc.). Steel high speed in his letter of designation have P (starts with the designation of steel), followed by a number indicating the average tungsten content, and then letters and numbers which determine the mass content of elements. Not indicate the content of chromium, since it is stable around 4% of all high speed steel and carbon, since the latter always in proportion to the content of vanadium. It should be noted that if the vanadium content exceeds 2.5%, the letter Let the numbers indicate, (for example, steel R6M5 and P6 M5F3). Stainless steel standard, according to GOST 5632-72, mark the letters and numbers on the principle adopted for structural alloy steels (for example, or 08Kh18N10T 16H18N12S4TYUL).