Grades of stainless steel and heat-resistant steel, with specified alloying element symbols and Arabic numerals. Generally in the head of the grade with an Arabic number to indicate the average carbon content (in a few thousand) more than the average carbon content is less than one dry part of the "0", carbon content is not more than 0.03% (that is, ultra-low carbon steel), with "00". When the average alloy content is less than 1.50%, only the element symbol is indicated in the grade, and generally the content is not indicated. The average alloy content is 1. 50~2.49%, 2.50~3.49%...... 22.50 ~ 23.49%... When, write 2, 3...... accordingly 23... . Special-purpose or free-cutting stainless steels and heat-resistant steels preceded by a special symbol for special-purpose or free-cutting steels. Such as:
2Cr13: represents the average carbon content of 0.20% average chromium content of 13% chromium stainless steel,
0Cr18NiLoti: low carbon chromium-nickel stainless steel with an average chromium 18%, nickel L0% and titanium content less than 0.10% carbon but greater than 0.03%;
00Cr19NiL0: represents the carbon content of less than 0.03% average chromium 19%, nickel LO % of ultra-low carbon chromium nickel stainless steel;
Y1Cr18Ni9Se: means an average carbon content of 0.10% average chromium content of 18%, nickel content of 9% and free cutting element selenium free cutting chrome-nickel stainless steel;
ML1CrL8Ni12: denotes the average carbon content of 0.10% of the average chromium content of 18%, nickel content of 12% for cold top forging (that is, for riveting nickel stainless steel;
5Cr21Mn9Ni4N: represents the cast Mn-Ni type heat resistant steel with an average carbon content of 0.50% and an average chromium content of 21%, manganese content of 9%, nickel content of 4% and nitrogen content;
