Sep 26 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesThermal PropertiesOther Designations
Introduction
Alloy steels are steels containing elements such as chromium, cobalt, nickel. They also contain a variety of steels with compositions that exceed the limitations of Si, Va, Cr, Ni, Mo, Mn, B and C allocated for carbon steels.
Alloy steels are used in specific melting and deoxidization processes for particular kind of applications. When compared with carbon steels, the alloy steels are a lot more responsive to mechanical and heat treatments.
The following datasheet provides an overview of AISI 8650 alloy steel.
Chemical Composition
The chemical composition of AISI 8650 alloy steel is outlined in the following table.
| Element |
Content (%) |
| Iron, Fe |
96.54-97.67 |
| Manganese, Mn |
0.750-1.00 |
| Carbon, C |
0.480-0.530 |
| Nickel, Ni |
0.400-0.700 |
| Chromium, Cr |
0.400-0.600 |
| Silicon, Si |
0.150-0.300 |
| Molybdenum, Mo |
0.150-0.250 |
| Sulfur, S |
≤ 0.0450 |
| Phosphorous, P |
≤ 0.0350 |
Physical Properties
The following table shows the physical properties of AISI 8650 alloy steel.
| Properties |
Metric |
Imperial |
| Density |
7.85 g/cm3 |
0.284 lb/in³ |
Mechanical Properties
The mechanical properties of AISI 8650 alloy steel are displayed in the following table.
| Properties |
Metric |
Imperial |
| Tensile strength |
715 MPa |
104000 psi |
| Yield strength |
385 MPa |
55800 psi |
| Bulk modulus (typical for steel) |
140 GPa |
20300 ksi |
| Shear modulus (typical for steel) |
80.0 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) |
22.50% |
22.50% |
| Hardness, Brinell |
212 |
212 |
| Hardness, Knoop (converted from Brinell hardness) |
235 |
235 |
| Hardness, Rockwell B (converted from Brinell hardness) |
94 |
94 |
| Hardness, Rockwell C (converted from Brinell hardness, value below normal HRC range, for comparison only) |
16 |
16 |
| Hardness, Vickers (converted from Brinell hardness) |
223 |
223 |
| Machinability (annealed and cold drawn, based on 100 machinability for AISI 1212 steel) |
60 |
60 |
Thermal Properties
The thermal properties of AISI 8650 alloy steel are given in the following table.
| Properties |
Metric |
Imperial |
| Thermal conductivity (typical steel) |
46.6 W/mK |
323 BTU in/hr.ft².°F |
Other Designations
Equivalent materials to AISI 8650 alloy steel are:
- ASTM A322
- ASTM A505
- ASTM A519
- SAE J404
- SAE J412
- SAE J770