In the high-precision machinery industry, the reliability of a bearing is only as good as the steel it is made from. GCr15-A, a high-carbon chromium bearing steel, is the most widely utilized material for manufacturing bearing rings, rolling elements, and high-load structural parts.
At Chinaspecsteel, we leverage the advanced metallurgy of Jiyuan Iron & Steel Group to provide GCr15-A wire rods characterized by extreme cleanliness, uniform microstructure, and exceptional fatigue life.
What is GCr15-A Bearing Steel?
GCr15-A (where “A” denotes high-quality grade) is a specialized alloy steel featuring approximately 1% Carbon and 1.5% Chromium. The addition of Chromium ensures high hardenability and wear resistance, while the “A” grade signifies stricter control over impurities like Phosphorus (P) and Sulfur (S).
International Equivalents
To facilitate global procurement, GCr15-A is technically equivalent to:
- USA: AISI 52100 / SAE 52100
- Germany: DIN 100Cr6 (1.3505)
- Japan: JIS G4805 SUJ2
- ISO: ISO 683-17
Technical Specifications & Chemical Composition
The performance of GCr15-A depends on the precision of its chemical balance. Our production process utilizes LF+VD vacuum degassing to ensure the lowest possible oxygen content, which is critical for preventing contact fatigue.
| Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | Chromium (Cr) | Phosphorus (P) | Sulfur (S) |
|---|---|---|---|---|---|---|
| Content (%) | 0.95 – 1.05 | 0.15 – 0.35 | 0.25 – 0.45 | 1.40 – 1.65 | ≤ 0.025 | ≤ 0.020 |
Key Quality Metrics: Why “A” Grade Matters
For B2B buyers, the “A” suffix in GCr15-A represents a commitment to superior internal quality:
- Non-Metallic Inclusions: We strictly control oxide and sulfide inclusions. Low inclusion levels are the primary factor in extending the “L10” fatigue life of bearings.
- Carbide Uniformity: Through controlled rolling and cooling, we ensure that carbides are small and evenly distributed, preventing stress concentration points.
- Spheroidizing Annealing: Our GCr15-A wire rods are typically supplied in a spheroidized annealed state to provide optimal machinability and a perfect starting structure for final quenching.
- Decarburization Control: Minimizing surface decarburization is essential to ensure the surface hardness of the finished bearing after heat treatment.
Industrial Applications
GCr15-A wire rods from Chinaspecsteel are the preferred raw material for:
- Bearing Rings & Balls: For automotive, aerospace, and industrial motors.
- High-Load Rollers: Used in railway and wind power gearboxes.
- Precision Tooling: Cold work dies and measuring tools requiring extreme hardness (HRC 60-65 after treatment).
- Fuel Injection Systems: Components requiring high pressure resistance and wear stability.
The Chinaspecsteel Supply Advantage
As the export arm for Jiyuan Steel, we bridge the gap between mill-scale production and global quality requirements:
- Billet Inspection: 100% ultrasonic testing of billets to ensure zero internal defects before rolling.
- Advanced Rolling: Our high-speed wire rod mills produce diameters from 5.5mm to 30mm with tight dimensional tolerances.
- Certifications: Full compliance with IATF 16949 (Automotive Quality Management) and ISO 9001.
- Expert Logistics: Seaworthy packaging with VCI (Volatile Corrosion Inhibitor) protection to prevent rust during sea transit.
FAQ: Sourcing GCr15-A Bearing Steel
1. What is the difference between GCr15 and GCr15-A?
GCr15-A is the “High-Quality” version, featuring lower limits for Phosphorus (P) and Sulfur (S) and stricter control over non-metallic inclusions compared to standard GCr15.
2. Is GCr15-A the same as AISI 52100?
Yes, they are chemically and functionally equivalent. GCr15-A is the Chinese standard designation (GB/T 18254), while AISI 52100 is the American standard.
3. What is the typical delivery state of the wire rod?
We usually supply GCr15-A in the Spheroidized Annealed (+AC) condition to ensure the material is soft enough for cold drawing or machining.
4. How do you ensure low oxygen content?
We use VD (Vacuum Degassing) or VOD processes during refining to keep oxygen levels typically below 10-12 ppm, significantly enhancing fatigue resistance.
5. What surface defects do you test for?
Every coil undergoes eddy current testing and visual inspection to ensure no cracks, folds, or surface inclusions are present.
6. What is the hardness of GCr15-A after spheroidizing annealing?
The hardness is typically controlled at HBW ≤ 207, providing an ideal balance for subsequent processing.
7. Can GCr15-A be used for high-temperature applications?
GCr15-A is best suited for working temperatures up to 120°C. For higher temperatures, specialized high-temperature bearing steels (like Cr4Mo4V) are recommended.
8. What coil sizes are available?
Standard coils are 2.0 MT to 2.5 MT. We can provide customized coil weights based on your handling equipment requirements.
9. Do you provide a Mill Test Certificate (MTC) with every shipment?
Yes, we provide MTCs according to EN 10204 3.1, including chemical analysis, grain size, inclusion ratings, and mechanical test results.
10. How do you handle rust prevention for long-distance shipping?
We use high-quality anti-rust oil and wrap the coils in multiple layers of waterproof paper and plastic film, often including desiccants for moisture-sensitive routes.
Specialized Supply: For high-efficiency transformer cores, we provide premium Grain Oriented Electrical Steel (GOES). Click here to explore our full range of grades and technical specifications.
English