4340 round bar is a medium carbon, low alloy steel known for its toughness and strength due to its relatively large portion. AISI 4340 is also a nickel chromium molybdenum steel. In the tensile range of 930-1080 mpa, 4340 alloy steel is usually provided and tempered. Pre-hardened and tempered 4340 steel can be further surface hardened by flame or induction hardening and nitriding. 4340 steel has good impact and impact resistance as well as wear and wear resistance under hardening conditions. AISI 4340 steel properties provide good ductility under annealing conditions, causing it to bend or form. Our 4340 alloy steel can also be melted and resistance welded. ASTM 4340 materials are commonly used, where other alloy steels are not hardenable to provide the required strength. It is an excellent choice for highly stressful parts. AISI 4340 alloy steel can also be machined by all customary methods.
4340 round bar is an ultra-high strength steel classified a medium-carbon, low-alloy steel. 4340 steel has high strength, ductility, toughness, creep resistance, and fatigue resistance relative to most other steels. Hardness ranging from 24 to 53 HRC can be achieved, depending on the heat treatment.The mechanical properties of 4340 are highly dependent on the heat treatment. 4340 can commonly have yield strengths of 740-1860 MPa, tensile strengths of 860-1980 MPa, elongations of 11-23%, and plane strain fracture toughness of 53-110 MPa√m.
Applications of 4340 round steel bar include heavy shafting, fasteners, aircraft, automotive, and hydraulic systems.