The numbering and indicating methods use the symbols of the world's chemical elements and national symbols to indicate the chemical composition, and the Arabic alphabet to indicate the content of ingredients. For example, China and Russia use fixed-digit numbers to indicate steel series or numbers; The series, the 400 series, and the 200 series are composed of Latin letters and order, and only indicate the use.
China's numbering rules ①Use element symbols ②Use, Pinyin, open hearth steel: P, boiling steel: F, killed steel: B, class A steel: A, T8: special 8, ball, joint steel, spring steel, such : 20CrMnTi 60SiMn, (indicating the content of C in tens of thousands of stainless steel, alloy tool steel (indicating the content of C in parts per thousand).
Such as: 1Cr18Ni9 thousandths (that is, C percent), stainless C≤0.08 percent, such as 0Cr18Ni9, ultra-low carbon C≤0.03 percent, such as the world stainless steel marking method, the American Iron and Steel Institute uses three digits Various specifications of malleable stainless steel. During this period, austenitic stainless steel is marked with 200 and 300 series numbers, and ferritic and martensitic stainless steel is marked with 400 series numbers.
For example, some more general austenitic stainless steels are marked with 201, 304, 316, and 310, ferritic stainless steels are marked with 430 and 446, and martensitic stainless steels are marked with 410, 420, and 440C. Phase (austenitic-ferrite), stainless steel, deposition hardened stainless steel, and high alloys with less than 50% iron content are usually selected by patent titles or trademarks.
