Stainless steel numbering principle
1. Use international chemical element symbols and national symbols to represent chemical components, and Arabic letters to represent component content:
Such as: China, Russia 12CrNi3A
2. Use fixed-digit numbers to represent steel series or numbers; such as: the United States, Japan, 300 series, 400 series, 200 series;
3. The serial number is composed of Latin letters and sequence, which only indicates purpose.
4. my country’s numbering rules
①Use element symbols
②Purpose, Chinese pinyin, open hearth steel: P, boiling steel: F, killed steel: B, Class A steel: A, T8: special 8, GCr15: ball
◆Composite steel, spring steel, such as: 20CrMnTi 60SiMn, (use a few ten thousandths to express the C content)
◆Stainless steel springs, alloy spring tool steels (using a few thousandths to express C content), such as: 1Cr18Ni9 one thousandth (ie 0.1% C), stainless C ≤ 0.08% such as 0Cr18Ni9, ultra-low carbon C ≤ 0.03% such as 0Cr17Ni13Mo
5. International stainless steel marking method
The American Iron and Steel Institute uses three digits to indicate various standard grades of forgeable stainless steel. among them:
①Austenitic stainless steel is marked with 200 and 300 series numbers;
②Ferritic and martensitic stainless steels are represented by 400 series numbers. For example, some of the more common austenitic stainless steels are marked with 201, 304, 316 and 310;
③Ferritic stainless steel is marked with 430 and 446, and martensitic stainless steel is marked with 410, 420 and 440C, duplex (austenite-ferrite);
④Stainless steel, precipitation hardening stainless steel and high alloys with iron content less than 50% are usually named by patent names or trademarks.