Sep 13 2012
Topics Covered
IntroductionChemical CompositionPhysical PropertiesMechanical PropertiesThermal PropertiesOther DesignationsApplications
Introduction
Alloy steels contain a wide range of steels whose compositions exceed the limitations of C, Mo, Cr, Va, Mn, Ni, Si, and B fixed for carbon steels. These steels are more responsive to mechanical and heat treatments than carbon steels.
AISI 8620 alloy steel is a common, carburizing alloy steel. This alloy steel is flexible during hardening treatments, thus enabling improvement of case/core properties. The following datasheet will provide more details about AISI 8620 alloy steel.
Chemical Composition
The following table shows the chemical composition of AISI 8620 alloy steel.
| Element |
Content (%) |
| Iron, Fe |
96.895-98.02 |
| Manganese, Mn |
0.700-0.900 |
| Nickel, Ni |
0.400-0.700 |
| Chromium, Cr |
0.400-0.600 |
| Carbon, C |
0.180-0.230 |
| Silicon, Si |
0.150-0.350 |
| Molybdenum, Mo |
0.150-0.250 |
| Sulfur, S |
≤ 0.0400 |
| Phosphorous, P |
≤ 0.0350 |
Physical Properties
The physical properties of AISI 8620 alloy steel are outlined in the following table.
| Properties |
Metric |
Imperial |
| Density |
7.85 g/cm3 |
0.284 lb/in³ |
Mechanical Properties
The mechanical properties of annealed AISI 8620 alloy steel are outlined in the table below.
| Properties |
Metric |
Imperial |
| Tensile strength |
530 MPa |
76900 psi |
| Yield strength |
385 MPa |
55800 psi |
| Elastic modulus |
190-210 GPa |
27557-30458 ksi |
| Bulk modulus (typical for steel) |
140 GPa |
20300 ksi |
| Shear modulus (typical for steel) |
80 GPa |
11600 ksi |
| Poisson’s ratio |
0.27-0.30 |
0.27-0.30 |
| Izod Impact |
115 J |
84.8 ft.lb |
| Hardness, Brinell |
149 |
149 |
| Hardness, Knoop (converted from Brinell hardness) |
169 |
169 |
| Hardness, Rockwell B (converted from Brinell hardness) |
80 |
80 |
| Hardness, Vickers (converted from Brinell hardness) |
155 |
155 |
| Machinability (hot rolled and cold drawn, based on 100 machinability for AISI 1212 steel) |
65 |
65 |
Thermal Properties
The thermal properties of AISI 8620 alloy steel are highlighted below.
| Properties |
Metric |
Imperial |
| Thermal conductivity |
46.6 W/mK |
323 BTU in/hr.ft².°F |
Other Designations
Equivalent materials to AISI 8620 alloy steel are outlined in the table below.
| AISI 8620 |
AMS 6274 |
AMS 6276 |
AMS 6277 |
AMS 6375 |
ASTM A29 |
| ASTM A322 |
ASTM A331 |
ASTM A506 |
ASTM A507 |
ASTM A513 |
ASTM A519 |
| ASTM A646 |
ASTM A752 |
ASTM A829 |
MIL S-8690 |
SAE J1397 |
SAE J404 |
| AFNOR 20 NCD 2 |
AFNOR 22 NCD 2 |
DIN 1.6523 |
UNI 20 NiCrMo 2 |
JIS SNCM 21 |
JIS SNCM 21 H |
| B.S. 805 H 20 |
B.S. 805 M 20 |
AMS 6274G |
AMS 6276C |
AMS 6277A |
ASTM A505 |
| MIL SPEC MIL-S-16974 |
SAE J404 |
SAE J770 |
|
|
|
|
|
|
|
|
|
Applications
The AISI 8620 can be used for a number of medium-strength applications such as camshafts, fasteners, gears, and chains/chain pins.