AISI/ASTM 52100 bearing steel is a high carbon, chromium containing low alloy steel that is through hardening and noted in particular for use as bearings.
52100 bearing steel is one kind of special steel with features of high wear resistance and rolling fatigue strength. High-carbon chromium bearing steel, engineering steel and some types of stainless steel and heat resistant steel are used as materials of bearings and for other purposes.
Advantages of Chrome Bearing Steel 52100:
Superior hardness, 60-67 on Rockwell hardness scale at room temperature
High carbon chrome alloy steel
Operates continually at temperatures up to 120°C
Used to produce precision ball bearings and roller bearings
Cost-effective
Long working life
1. Supply Range of ASTM 52100 Bearing Steel
AISI 52100 Steel Round Bar: diameter 8mm – 800mm
Process: Cold drawn, hot rolled, forged etc.
Surface Finish: black, rough machined, turned, polished or as per given requirements.
2. Relevant Steel Specification of ASTM 52100 Bearing Steel
| Country | USA | Germany | Japan | British |
| Standard | ASTM A295 | DIN 17230 | JIS G4805 | BS 970 |
| Grade | 52100 | 100Cr6/1.3505 | SUJ2 | 535A99/EN31 |
3. Chemical compositions of 52100 bearing steel and equivalents
| Standard | Grade | C | Mn | P | S | Si | Ni | Cr | Cu | Mo |
| ASTM A295 | 52100 | 0.93-1.05 | 0.25-0.45 | 0.025 | 0.015 | 0.15-0.35 | 0.25 | 1.35-1.60 | 0.30 | 0.10 |
| DIN 17230 | 100Cr6/1.3505 | 0.90-1.05 | 0.25-0.45 | 0.030 | 0.025 | 0.15-0.35 | 0.30 | 1.35-1.65 | 0.30 | – |
| JIS G4805 | SUJ2 | 0.95-1.10 | 0.50 | 0.025 | 0.025 | 0.15-0.35 | – | 1.30-1.60 | - | - |
| BS 970 | 535A99/EN31 | 0.95-1.10 | 0.40-0.70 | - | - | 0.10-0.35 | - | 1.20-1.60 | - | - |
4. Mechanical Properties of ASTM A295 52100 Bearing Steel
| 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) | 8484 | 8484 |
| Machinability (spheroidized annealed and cold drawn. Based on 100 machinability for AISI 1212 steel) | 40 | 40 |
52100 Steel Physical Properties
| Properties | Metric | Imperial |
| Density | 7.81 g/cm3 | 0.282 lb/in³ |
| Melting point | 1424°C | 2595°F |
52100 Alloy Steel Thermal Properties
| 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 |
5. Forging of A295 52100 Bearing Steel
AISI 52100 alloy steel is forged at 927 to 1205°C, and should not be forged below 925ºC. A post-forge equalization treatment is recommended at 745ºC for 4-6 hours followed by air cooling for SAE/AISI 52100 steel.
6. Heat Treatment for ASTM 52100 Bearing Steel
ASTM/AISI 52100 alloy bearing steel is heated at 816°C followed by quenching in oil. Before performing this process, it is subjected to normalizing heat treatment at 872°C followed by slowly cooling in order to reduce the machining stress.
Hot Working
AISI 52100 bearing steels alloy can be hot worked at 205 to 538°C.
Cold Working
AISI 52100 bearing steel can be cold worked using conventional techniques in the annealed or normalized conditions.
Annealing
For spheroidize annealing, the following isothermal anneal is recommended:
1500ºF (815ºC) for 3 hours
1350ºF (735ºC) for 4 hours
1250ºF (675ºC) for 3 hours
Slow cool to 1000ºF (540ºC) then air cool.
Quenching
AISI 52100 alloy bearing steel could be hardened by quenching in water from 801-829 degree or quench in oil from 816-842 degree.
Tempering
Temper to desired hardness as indicated by tempering curves after water or oil quench.
7. Applications of 52100 Bearing Steel
Alloy steel 52100 grade bearing steel is mainly used for the manufacture of aircraft bearings and other highly stressed parts. This steel grade 52100 steel is preferably vacuum arc re-melted to give optimum performance.
Typical applications: Bearing Manufacture, CV joints, ball screws, gauges, knife etc.
Product size range
Diameter: 40mm - 150mm
Length: on request
Production Process
Key clients
