4340 SCM439 34CrNiMo6 quenched & tempered steel bar 

4340 SCM439 34CrNiMo6 quenched and tempered steel round bar 4340 scm439 43CrNiMo6 steel is one kind of Chromium nickel molybdenum steel known for it's toughness and ti's ability to attach high strength after heat treatment to produce commercial and aircraft, automobile systems, forged hydraulic and other machine tools like forged steel crankshafts. 4340 steel round bar is kind of alloy steel round bar in standard AISI, ASTM or SAE standard. SCM439 steel round bar is in JIS standard. 4340 scm439 43CrNiMo6 steel material quenched and tempered q&t steel bar we supply includes following advangtages: Consistent mechanical properties Deep mechanical properties (from surface to the center according to your requirement) Even hardness on the whole bars/Tougher and Increased strength No brittle, UT testing/Precision size tolerance/Good straightness Good Roughness/Professional technical service/Competitive price/Fast delivery  Ais…