AISI T15 Balls
Ball Bearing
High-Speed Steel, Ultra Wear-Resistant & Heat-Tolerant
AISI T15 balls from Atlas Ball & Bearing are precision balls manufactured from premium tungsten–molybdenum high-speed steel, designed for extreme wear resistance, superior hardness, and excellent heat stability. These balls are ideal for tooling, industrial, and high-friction applications where maximum durability and dimensional accuracy are critical.
Produced from high-quality AISI T15 tool steel, these balls retain hardness at elevated temperatures and perform reliably under heavy loads and abrasive conditions, outperforming standard steels in severe working environments.
150
Precision Ball Diameter
Why Choose AISI T15 Balls?
AISI T15 is a tungsten–molybdenum high-speed tool steel known for its extreme hardness, abrasion resistance, and hot hardness. It is especially suited for high-wear applications where conventional steels soften under heat.
AISI T15 balls provide exceptional wear life, high compressive strength, and dimensional stability, making them a preferred choice for tooling, cutting, and heavy-duty mechanical components.
Key Benefits
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Extremely high hardness and wear resistance
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Excellent hot hardness and heat tolerance
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Superior abrasion and fatigue resistance
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High compressive strength for demanding applications
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Stable dimensional accuracy under load
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Long service life in severe-duty conditions
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Suitable for tooling, high-speed, and high-load components
Manufacturing & Supply
We are capable of manufacturing and supplying loose AISI T15 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 T15 balls are widely used in environments requiring extreme wear resistance and heat tolerance.
Typical applications include:
Tooling and cutting equipment
High-speed, high-load industrial machinery
Precision bearings in abrasive environments
Wear-critical components
Aerospace and automotive tooling systems
Heavy engineering and metalworking applications
AISI T15 balls are available in multiple sizes and tolerances to meet high-performance and precision-critical requirements.
Why Atlas Ball & Bearing?
UK-based manufacturer and worldwide supplier of precision steel balls
Extensive stock with rapid UK and international delivery
Wide range of sizes, grades, and tolerances
Expertise in tungsten and molybdenum high-speed steels
Consistent quality, surface finish, and full 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!