AISI S2 Balls
Ball Bearing
Shock-Resistant Tool Steel, Tough & Impact-Resistant
AISI S2 balls from Atlas Ball & Bearing are precision-engineered from high-quality shock-resistant tool steel, designed to deliver exceptional toughness, impact resistance, and durability. These balls are ideal for applications where components are exposed to heavy loads, sudden impacts, and high-stress conditions.
Manufactured from premium AISI S2 steel, these balls offer excellent resistance to deformation and fatigue, making them a reliable choice for demanding mechanical and industrial environments where strength and resilience are critical.
150
Precision Ball Diameter
Why Choose AISI S2 Balls?
AISI S2 is a shock-resistant tool steel known for its outstanding toughness and ability to withstand impact without cracking or failing. Unlike high-speed steels that prioritise hardness, S2 offers a balance of strength, flexibility, and fatigue resistance.
AISI S2 balls are particularly suited to applications where sudden loads, vibration, and mechanical shock are common, providing long service life and dependable performance under stress.
Key Benefits
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Exceptional toughness and shock resistance
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High impact strength and durability
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Good wear resistance under dynamic loads
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Excellent resistance to cracking under stress
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Strong fatigue resistance
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Reliable performance in high-stress environments
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Ideal for heavy-duty and impact-driven applications
Manufacturing & Supply
We are capable of manufacturing and supplying loose AISI S2 steel balls in nearly every variation of grade, maintaining an extensive stock with sizes ranging from 0.2mm to 150mm in diameter.
Please feel free to rate our products and service or send us your comments by using our form opposite →
Additionally, we offer a bespoke ball manufacturing service, which follows the same process controls and traceability but uses a customer’s own material. For further details, please email us or call +44 (0) 1922 710515.
Applications
AISI S2 balls are widely used in environments where impact resistance and toughness are essential.
Typical applications include:
- Impact tools and tooling components
- Heavy-duty industrial machinery
- Shock-loaded mechanical systems
- Automotive and engineering components
- Construction and mining equipment
- High-stress and vibration-prone environments
AISI S2 balls are available in a variety of sizes and tolerances to meet both general-purpose and precision engineering requirements.
Why Atlas Ball & Bearing?
- UK-based manufacturer and global supplier of precision steel balls
- Extensive stock with fast UK and international delivery
- Wide range of sizes, grades, and tolerances
- Expertise in shock-resistant tool steels
- Consistent quality, surface finish, and full material traceability
Related Materials

Useful terms and definitions
Batch or Lot:
A defined quantity of balls manufactured under conditions presumed to be uniform and which is considered an entity.
Nominal Ball Diameter:
The diameter value that is used for the general identification of a ball size.
Single Ball Diameter:
The distance between two parallel planes tangential to the actual ball surface.
Diameter Tolerance per Batch:
The allowed difference between the smallest measured ball diameter and the largest ball diameter within the same batch or lot quantity.
Sphericity:
A measure of roundness expressed as the difference between the measured roundness of a ball and a theoretically perfectly round ball.
Surface Finish or Roughness:
A measure of the texture of a surface. It is quantified by the vertical deviations of the actual surface from its ideal form. If these deviations are large, the surface is rough; if they are small, the surface is smooth.
Ball Grades
| Grade | Diameter Tolerance per Ball | Sphericity | Diameter Tolerance per Unit Container | Basic Diameter Tolerance | Maximum Surface Roughness Micro | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Inch | µ | Inch | µ | Inch | µ | Inch | µ | Inch | µ | |
| 3 | .000003 | 0.076 | .000003 | 0.076 | .000005 | 0.127 | ±.00003 | ± 0.076 | 0.5 | 0.013 |
| More details about Grade 3... | ||||||||||
| 5 | .000005 | 0.127 | .000005 | 0.127 | .00001 | 0.25 | ±.00005 | ± 0.127 | 0.8 | 0.02 |
| More details about Grade 5... | ||||||||||
| 10 | .000010 | 0.25 | .000010 | 0.25 | .00002 | 0.51 | ±.0001 | ± 2.5 | 1.0 | 0.025 |
| More details about Grade 10... | ||||||||||
| 15 | .000015 | 0.38 | .000015 | 0.38 | .00003 | 0.76 | ±.0001 | ± 2.5 | 1.2 | 0.03 |
| More details about Grade 15... | ||||||||||
| 25 | .000025 | 0.63 | .000025 | 0.63 | .00005 | 1.27 | ±.0001 | ± 2.5 | 1.5 | 0.038 |
| More details about Grade 25... | ||||||||||
| 50 | .00005 | 1.27 | .00005 | 1.27 | .0001 | 2.5 | ±.0002 | ± 5 | 3.0 | 0.075 |
| More details about Grade 50... | ||||||||||
| 100 | .0001 | 2.5 | .0001 | 2.5 | .0002 | 5 | ±.0005 | ± 5 | 5.0 | 0.125 |
| More details about Grade 100... | ||||||||||
| 200 | .0002 | 5 | .0002 | 5 | .0004 | 10 | ±.0010 | ± 10 | 8.0 | 0.2 |
| More details about Grade 200... | ||||||||||
| 300 | .0003 | 7.5 | .0003 | 7.5 | .0006 | 15 | ±.0015 | ± 37.5 | N/A | N/A |
| More details about Grade 300... | ||||||||||
| 500 | .0005 | 12.5 | .0005 | 12.5 | .001 | 25 | ±.002 | ± 50 | N/A | N/A |
| More details about Grade 500... | ||||||||||
| 1000 | .001 | 25 | .001 | 25 | .002 | 50 | ±.005 | ± 125 | Not Applicable | Not Applicable |
| More details about Grade 1000... | ||||||||||
| 2000 | .002 | 50 | .002 | 50 | .004 | 100 | ±.005 | ± 125 | N/A | N/A |
| More details about Grade 2000... | ||||||||||
Sample Our Work!
Take the first step towards precision and quality with our expert services. At Atlas Ball & Bearing, we’re committed to delivering top-notch precision balls and rollers for a wide range of industries, including gas, oil, medical, and transportation. Our dedicated team is ready to assist you with custom solutions tailored to your specific needs. Experience the Atlas Ball & Bearing difference now!