4140 / 4142 Hot Rolled Bar

4140 / 4142 Hot Rolled Bar

Characteristics

HR 4140 / 4142 alloy steel bar is a medium carbon, chromium-molybdenum, through-hardening alloy steel that has a good hardenability with high strength and toughness as well as good fatigue and impact resistance after heat treating.  It can be readily nitrided for improved surface wear.  For best machining, it is often used in the annealed condition; however, when the amount of machining necessary is minimal or when the risk of distortion in heat treating a finished part is paramount, it is typically used in the quenched and tempered condition.  

Applications

Typical applications for 4140 and 4142 HR bar are sprockets, bolts, chain pins, drill collars, universal joints, highly stressed parts or parts subject to severe wear.

Sizes

  • Diameter: 0.125" thru 12"
  • Stock Lengths: 10' thru 24'

Typical Chemical Properties

Carbon

0.38 - 0.45

Manganese

0.75 - 1.00

Phosphorus, Max %

0.035

Sulfur, Max %

0.040

Silicon

0.15 - 0.35

Chromium

0.80 - 1.10

Molybdenum

0.15 - 0.25

Typical Mechanical Properties for Annealed

Tensile Strength ksi

90k - 100k

Yield Strength

60k - 70k

Elongation in 2"

20% - 30%

Reduction of area

50% - 60%

Brinelle Hardness

185 - 210

Typical Mechanical Properties for Heat Treated

Tensile Strength ksi

130k

Yield Strength

110k

Elongation in 2"

16%

Reduction of area

50%

For inquiries, call us today at 800-861-8272.