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4340 Cold Drawn Steel Bar

Cold drawn 4340 steel bar is widely used throughout the aerospace industry because of its high strength and ductility. This grade is a medium carbon, nickel-chromium-molybdenum steel that has good shock and impact resistance. Cold drawn 4340 bar is utilized in a variety of high-stress applications due to its toughness and good fatigue strength when heat treated. Eaton Steel Bar Company stocks several diameters of this grade to meet your demands quickly. We supply cold drawn 4340 steel bar to various industries like aerospace, automotive, and more.

4340 cold-rolled-steel-bar

Applications

Typical applications for this grade include gears, drilling parts, and shafts.

Requirements

Eaton Steel Bar Company can meet the following specifications for this grade:

  • ASTM A108
  • ASTM A322

Shapes and Sizes

Eaton Steel Bar Company supplies 4340 cold drawn steel bar in a variety of sizes ranging from – 1 ½”-11”. The shapes available for this grade include:

  • Rounds

Standard "4340 Grade" Chemical Composition

Carbon 0.38-0.43
Manganese 0.60-0.80
Phosphorus (max) 0.035
Sulfur (max) 0.040
Silicon 0.15-0.35
Nickel 1.65-2.00
Chromium 0.70-0.90
Molybdenum 0.20-0.30

 

Estimated Mechanical Property Ranges for "Grade 4340 Annealed"

Tensile strength (psi) 100,000 - 110,000
Yield strength (psi) 90,000 - 100,000
Elongation in 2” (%) 15 - 25
Reduction of area (%) 50 - 60
Brinell Hardness (BHN) 210 - 240