AISI/SAE 4340 Alloy Steel Bar

SKU: HC-1137084775220977664

AISI 4340 carbon steel bar is made of a heat treatable low alloy steel containing chromium, nickel and molybdenum. It has high toughness and high strength under heat treatment conditions.

Testing & Certification

Key Features

  • Third-Party Inspection Support
  • Sufficient Inventory Supply
  • International Standard Certification
  • Custom Processing Service

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Product Description

AISI 4340 carbon steel bar is made of a heat treatable low alloy steel containing chromium, nickel and molybdenum. It has high toughness and high strength under heat treatment conditions. AISI 4340 is a commonly used alloy steel with high strength, high toughness, good wear resistance and corrosion resistance. Its moderate carbon content gives it good machinability and weldability. In addition, it also contains appropriate amounts of chromium, nickel and other elements, which further improves its performance. At the same time, its toughness and ductility are also quite good, and it can maintain good performance even in both high or low temperature environments. Due to the excellent physical and mechanical properties of 4340 steel, 4340 steel bars are also widely used in equipment manufacturing in corrosive environments such as petroleum, chemical industry, and ships.

Product Parameters

Product NameAISI/SAE 4340 Alloy Steel Bar
StandardEN / DIN / JIS / ASTM / BS / ASME / AISI,etc.
Common Round Bar Specifications3.0 - 50.8 mm,Over 50.8 - 300mm
Flat Steel Common Specifications6.35x12.7mm,6.35x25.4mm,12.7x25.4mm
Hexagon Bar Common SpecificationsAF5.8mm - 17mm
Square Bar Common SpecificationsAF2mm - 14mm,AF6.35mm,9.5mm,12.7mm,15.98mm,19.0mm,25.4mm
Length1 - 6 meters,Size Accept Custom
Diameter(mm)Hot Rolling R ound Bar25 - 600Cold Rolling Square Bar6 - 50.8
Hot Rolling Square Bar21 - 54Cold Rolling Hexagon Bar9.5 - 65
Cold Rolling Round bar6 - 101.6Forged Rebar200 - 1000
Surface ProcessBright,Polished,Black
Other ServicesMachining(cnc),Centerless Grinding(cg),Heat Treatment,Annealing,Pickling,Polishing,Rolling,Forging,Cutting,Bending,Small Machining,etc.

Chemical Composition

GradeMnSCPSiCrNi
AISI 43400.60-0.800.0350.38-0.430.040.15-0.350.70-0.901.65-2.00

Mechanical Properties

GradeTensile Strength kg f/mm2Yield Strength kg f/mm2Elongation %Hardness HB
AISI 4340≥ 100≥ 90≥ 16293-352
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