Alloy Steel AISI 4140 Forgings
4140, G41400
AISI 4140 alloy steel is a chromium-, molybdenum-, and manganese-containing low alloy steel. It has high fatigue strength, abrasion and impact resistance, toughness, and torsional strength.
Alloy steels are designated by AISI four-digit numbers and comprise different kinds of steels, each with a composition which exceeds the limitations of B, C, Mn, Mo, Ni, Si, Cr, and Va set for carbon steels.
Alloy Steel AISI 4140 Forgings Properties
UNS G41400 Forgings Chemical Requirements
| Element | Cr | Mn | C | Si | Mo | S | P | Fe |
|---|---|---|---|---|---|---|---|---|
| Content (%) | 0.80 - 1.10 | 0.75 - 1.0 | 0.380 - 0.430 | 0.15 - 0.30 | 0.15 - 0.25 | 0.040 | 0.035 | Balance |
UNS G41400 Forgings Mechanical Requirements
| Properties | Metric | Imperial |
|---|---|---|
| Tensile strength | 655 MPa | 95000 psi |
| Yield strength | 415 MPa | 60200 psi |
| Bulk modulus (typical for steel) | 140 GPa | 20300 ksi |
| Shear modulus (typical for steel) | 80 GPa | 11600 ksi |
| Elastic modulus | 190-210 GPa | 27557-30458 ksi |
| Poisson's ratio | 0.27-0.30 | 0.27-0.30 |
| Elongation at break (in 50 mm) | 25.70% | 25.70% |
| Hardness, Brinell | 197 | 197 |
| Hardness, Knoop (converted from Brinell hardness) | 219 | 219 |
| Hardness, Rockwell B (converted from Brinell hardness) | 92 | 92 |
| Hardness, Rockwell C (converted from Brinell hardness. Value below normal HRC range, for comparison purposes only) | 13 | 13 |
| Hardness, Vickers (converted from Brinell hardness) | 207 | 207 |
| Machinability (based on AISI 1212 as 100 machinability) | 65 | 65 |