Sep 26 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical properties
Thermal Properties
Fabrication and Heat Treatment
Machinability
Forming
Heat Treatment
Forging
Hot Working
Cold Working
Annealing
Hardening
Applications
Introduction
Alloy steels contain different varieties of steels that exceed the
composition limits of Mn, C, Mo, Si, Ni, Va, and B set for carbon
steels. They are designated by AISI four-digit numbers. They respond
more quickly to mechanical and heat treatments than carbon steels.
AISI 52100 alloy steel is known as a high carbon, chromium
containing low alloy steel. The following datasheet gives an overview
of AISI 52100 alloy steel.
Chemical Composition
The following table shows the chemical composition of AISI 52100
alloy steel.
| Element |
Content
(%) |
| Iron, Fe |
96.5 - 97.32 |
| Chromium, Cr |
1.30 - 1.60 |
| Carbon, C |
0.980 - 1.10 |
| Manganese, Mn |
0.250 - 0.450 |
| Silicon, Si |
0.150 - 0.300 |
| Sulfur, S |
≤ 0.0250 |
| Phosphorous, P |
≤ 0.0250 |
Physical Properties
The physical properties of AISI 52100 alloy steel are listed in the
following table.
| Properties |
Metric |
Imperial |
| Density |
7.81 g/cm3 |
0.282 lb/in³ |
| Melting point |
1424°C |
2595°F |
Mechanical properties
The mechanical properties of AISI 52100 alloy steel are outlined in
the following table.
| Properties |
Metric |
Imperial |
| 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 |
| Hardness, Brinell |
- |
- |
| Hardness, Knoop (converted from
Rockwell C hardness) |
875 |
875 |
| Hardness, Rockwell C (quenched in
oil from 150°C tempered) |
62 |
62 |
| Hardness, Rockwell C (quenched in
water from 150°C tempered) |
64 |
64 |
| Hardness, Rockwell C (quenched in
oil) |
64 |
64 |
| Hardness, Rockwell C (quenched in
water) |
66 |
66 |
| Hardness, Vickers (converted from
Rockwell C hardness) |
848 |
848 |
| Machinability (spheroidized
annealed and cold drawn. Based on 100 machinability for AISI 1212 steel) |
40 |
40 |
Thermal Properties
The thermal properties of AISI 52100 alloy steel are given in the
following table.
| Properties |
Metric |
Imperial |
| Thermal expansion co-efficient (@
23-280°C/73.4- 36°F, annealed) |
11.9 µm/m°C |
6.61 µin/in°F |
| Thermal conductivity (typical steel) |
46.6 W/mK |
323 BTU in/hr.ft².°F |
Fabrication and Heat Treatment
Machinability
AISI 52100 alloy steel can be machined using conventional
techniques. The machinability of this steel can be improved by
performing spherodizing annealing process at 649°C (1200°F) before
machining.
Forming
AISI 52100 alloy steel can be formed using all conventional
techniques such as cold forging or stamping and hot or cold upset
forming techniques.
Heat Treatment
AISI 52100 alloy steel is heated at 816°C (1500°F) followed by
quenching in oil. Before performing this process, it is subjected to
normalizing heat treatment at 872°C (1600°F) followed by slowly cooling
in order to reduce the machining stress.
Forging
AISI 52100 alloy steel is forged at 927 to 1205°C (1700 to 2200°F).
Hot Working
AISI 52100 alloy steel can be hot worked at 205 to 538°C (400 to
1000°F).
Cold Working
AISI 52100 alloy steel can be cold worked using conventional
techniques in the annealed or normalized conditions.
Annealing
AISI 52100 alloy steel is annealed at 872°C (1600°F) followed by
slowly cooling to reduce cold working or machining stress.
Hardening
AISI 52100 alloy steel is hardened by cold working, or heating and
quenching. It can be carburized at 913°C (1675°F) followed by
quenching. It is again heated at 788°C (1450°F) followed by quenching
for the second time.
Applications
AISI 52100 alloy steel is used in bearings in rotating machinery.