MEDIUM-CARBON CHROME-MOLYBDENUM STEEL WITH BETTER MACHINABILITY

摘要

FIELD: metallurgy.;SUBSTANCE: invention relates to ferrous metallurgy, particularly, to production of steels with specific machining properties used in commercial production of machinery critical parts. Steel has the following chemical composition, in wt %: carbon 0.27-0.33, silicon 0.17 -0.37, manganese 0.40 - 0.70, chromium 0.80 - 1.10, molybdenum 0.15 - 0.25, tin 0.05 -0.30, iron and impurities making the rest. Steel contains following substances as admixtures, in wt %: sulfur - not over 0.025, phosphorus - not over 0.025, nickel - not over 0.25. tin-to-nickel ratio makes 0.24 - 6.;EFFECT: better machinability.;3 cl, 2 tbl, 12 ex