Patent ID: 11396682

Abstract:
A free-cutting and non-quenched and tempered steel, comprising the following chemical elements by mass percentages: C: 0.35-0.45%, Si: 0.45-0.0.65%, Mn: 1.35-1.65%, S: 0.025-0.065%, V: 0.07-0.15%, Ti: 0.01-0.018%, N: 0.012-0.017%, Al: 0.015-0.035%, Ca: 0.0008-0.0025%, with the remaining being iron and other unavoidable impurities, wherein the S and Ca elements satisfy the relationship S/Ca=20-60. A manufacturing method of the free-cutting and non-quenched and tempered steel, comprising the following steps: (1) smelting and refining; (2) casting; (3) rolling; (4) forging; and (5) two-stage cooling.