Development and industrial production practice of nonquenched and tempered 27CrMn2VS steel
Non quenched and tempered steel has been widely used in fields such as machinery,automobiles,and wind power due to market demand.In developed countries such as Europe,America,and Japan,the production level of non quenched and tempered steel is mature and the application rate is high.However,in China,it developed relatively late,the application rate is low,and the import rate is high.A non quenched and tempered 27CrMn2VS steel(/%:0.22-0.35 C,0.20-0.40 Si,1.50-2.50 Mn,0.035-0.065 S,0.35-0.65 Cr,0.05-0.15 V)for engineering machinery was obtained through the design of chemical composition and production process flow(80 t converter→LF refining→VD vacuum→continuous casting).In industrial production,using molten iron with P≤0.15%and S≤0.35%and LF refin-ing 3 batches fed to S line,adopting electromagnetic stirring+light pressure reduction technology during the continuous casting process,cooling the rolled material slowly in a slow cooling pit after final rolling,and the obtained microstructure is bainite(accounting for 78-88%)+pearlite+ferrite.The non-metallic inclusion level is A fine≤2.5 grade,A coarse≤2.0 grade,B fine≤1.0 grade,B coarse≤1.5 grade,C class≤0.5 grade,D class≤0.5 grade,Ds≤0.5 grade.The yield strength is 1020～1050 MPa,and the tensile strength is 820～850 MPa.Continuous production of 5 heats with stable chemical com-position,high cleanliness,excellent internal and surface quality can be used to replace some traditional quenched and tem-pered steels.
nonquenched and tempered steelmicroalloy-strengtheninginclusioncontrolled rolling and cooling
万方数据
维普
