AISI 4140H

AISI 4140H

Alloy steel is steel alloyed with different elements in total amounts between 1 and 50% by weight to enhance its mechanical properties such as strength, hardness, toughness and wear resistance. Low-alloy steels, on the other hand, are used to achieve better hardenability, which in turn enhances other mechanical properties. AISI 4140H is an H-steel grade alloy steel, commonly called AISI 4140H chromium-molybdenum steel.

Chemical Composition


Element Content(%)
Iron, Fe 96.585 - 97.93
Chromium, Cr 0.75 - 1.2
Manganese, Mn 0.65 - 1.1
Carbon, C 0.37 - 0.44
Molybdenum, Mo 0.15 - 0.3
Silicon, Si 0.15 - 0.3
Sulfur, S ≤0.040
Phosphorous, P ≤0.035

Mechanical Properties


Properties Metric Imperial
Tensile strength 1150 MPa 167000 psi
Yield strength 1050 MPa 152000 psi
Modulus of elasticity 205 GPa 29700 ksi
Bulk modulus 140 GPa 20300 ksi
Shear modulus 80 GPa 11600 ksi
Poisson’s ratio 0.29 0.29
Elongation at break 17.50% 17.50%
Reduction of area 55% 55%
Hardness, Brinell 341 341
Hardness, Vickers 361 361
Hardness, Knoop 369 369
Hardness, Rockwell C 37 37
Hardness, Rockwell B 99 99

Sheets / Plates

Production Route Hot Rolled, Cold Rolled
Material Standard AISI, ASTM, ASME, DIN, BS, EN, ISO, JIS, GOST, SAE, IS & Custom Chemistry
Size Width from 100mm to 3000mm ; Length from 500mm to 12000mm
Thickness 0.1mm to 400mm
Delivery Condition As Rolled, Annealed, Quenched and Tempered, Normalized
Surface Finish Plain, Brushed, Cladded

AISI 4140H Equivalent Grade / Specifications

  • B.S. 708 A 42
  • B.S. 708 M 40
  • B.S. 709 M 40
  • ASTM A304
  • SAE J1268
  • SS 2244
  • JIS SCM 4
  • JIS SCM 4 H
  • DIN 1.7225
  • AFNOR 42 CD 4
  • UNI 40 CrMo 4
  • UNI 38 CrMo 4 KB

AISI 4140H Applications

  1. Structures in Buildings, bridges, railway stations
  2. Fabrication of pipeline components & Industrial equipment
  3. Construction of automotive bodies, warehouses, shipping containers
  4. Commercial appliances, etc.