Representation method of steel grade in China (V): Free cutting steel

Free cutting steel is represented by standard chemical element symbols, symbols specified in Table 1 and Arabic numerals. Arabic numerals indicate the average carbon content (in tens of thousands).

① For sulfur free cutting steel and sulfur and phosphorus free cutting steel, the free cutting element symbol is not added after the symbol “Y” and Arabic numerals. For example, the grade of free cutting steel with an average carbon content of 0.15% is expressed as “Y15”

② For sulfur or sulfur and phosphorus free cutting steel with high manganese content, manganese element symbol shall be added after the symbol “Y” and Arabic numerals;

For example, the grade of free cutting steel with average carbon content of 0.40% and manganese content of 1.20% ~ 1.55% is expressed as “y40mn”.

③ For free cutting steel containing free cutting elements such as calcium and lead, the symbol of free cutting element shall be added after the symbol “Y” and Arabic numerals. For example: “y15pb”, “y45ca”.