Product Description
As the world shifts towards sustainable transportation, electric
vehicles (EVs) have become a focal point in the automotive
industry. A critical component contributing to the efficiency and
durability of EVs is the use of advanced materials in their
manufacturing. One such material is silicon nitride, specifically
used in EV motor ceramic balls for electric vehicle bearings. This
article explores the significance of silicon nitride in EV
bearings, its advantages over traditional materials, and its impact
on the electric vehicle industry.
Silicon nitride (Si3N4) is a ceramic material known for its
remarkable mechanical properties, making it ideal for
high-performance applications. In the context of electric vehicles,
silicon nitride ceramic balls are used in bearings to enhance the
performance of EV motors and reduce wear and tear. These ceramic
balls offer a unique combination of mechanical strength, electrical
resistivity, and thermal stability, which are crucial for the
demanding environments of electric vehicle bearings.
Electrical Insulation: One of the most significant advantages of silicon nitride ceramic
balls is their inherent electrical resistivity. Unlike traditional
steel bearings, which can suffer from electrical arcing due to
charge build-up, silicon nitride prevents this phenomenon,
enhancing the longevity and reliability of the bearings.
Reduced Friction: Silicon nitride ceramic balls are extremely smooth, leading to
lower friction in the bearing assembly. This reduction in friction
not only improves the efficiency of the motor but also reduces the
need for frequent lubrication.
Lightweight and Durable: Weighing approximately 60% less than steel, silicon nitride
ceramic balls contribute to a lighter overall vehicle weight, which
can improve the vehicle's speed and efficiency. Additionally, their
hardness ensures rolling efficiency and durability, even under
shock loads.
Corrosion Resistance: Silicon nitride offers excellent resistance to corrosion and
chemicals, making it suitable for various environmental conditions.
High-Temperature Resistance: Capable of withstanding extreme temperatures, silicon nitride
ceramic balls maintain their integrity and performance even in
high-heat applications.
The integration of silicon nitride ceramic balls in EV bearings
significantly influences the performance and reliability of
electric vehicles. By reducing friction and preventing electrical
arcing, these ceramic balls enhance the efficiency and lifespan of
EV motors. This translates to longer service intervals, reduced
maintenance costs, and improved overall vehicle performance.
Several studies and industry reports highlight the growing adoption
of silicon nitride in the automotive sector. For instance,
CoorsTek's Cerbec® silicon nitride bearing balls have set industry
standards for high performance and quality. Their use in EV
traction motors has demonstrated increased high-speed capabilities
and reduced lubrication requirements, as noted in their technical
specifications.
Moreover, companies like LILY Bearing emphasize the role of silicon
nitride in advancing the electric vehicle industry. With over 20
years of experience in manufacturing ceramic bearings, LILY Bearing
underscores the material's advantages, such as high rigidity, low
thermal expansion, and excellent shock resistance, which are
critical for EV applications.
While silicon nitride ceramic balls offer numerous benefits, there
are challenges and considerations in their application. The
manufacturing process of these ceramic balls is complex and
requires precise control over material properties. Any defects,
such as surface or particle defects, can impact the fatigue life of
the bearings. Therefore, ongoing research and development are
essential to optimize manufacturing techniques and minimize
potential defects.
| Property | Silicon Nitride (Si3N4) | Steel (440C) | Zirconia (ZrO2) | Alumina (Al2O3) |
|---|
| Density (g/cm³) | 3.2 | 7.8 | 6.0 | 3.9 |
| Hardness (HV) | 1,400–1,600 | 700–900 | 1,200–1,300 | 1,500–1,800 |
| Fracture Toughness (MPa·m½) | 6–7 | 15–20 | 7–10 | 3–4 |
| Compressive Strength (GPa) | 2.5–3.5 | 2.0–2.5 | 2.0–2.3 | 2.0–3.0 |
●Description:
Silicon Nitride Ceramic Ball is the most ideal bearing ball for
bearing applications, due to the excellent properties of silicon
nitride ceramics, it has many irreplaceable advantages comparing to
traditional steel materials, such as: high mechanical strength, low
wear loss, good self-lubrication, low density, high corrosion
resistance, good electrical insulation etc.
Therefore, Silicon Nitride Balls are mostly used for some harsh
working conditions: high speed/super speed bearings, high precision
bearings, bearings in vacuum, high/low temperature bearings.
Moreover, Silicon Nitride Ceramic Balls can also used as valve ball
or measurement balls in chemical pumps/high temperature
pumps/metdering pumps.
●Physical Properties:
Chemical Composition: | Si3N4≥95% |
Bulk Density: | 3.2±0.05g/cm3 |
Elastic Modulus: | 350GPa |
Hardness Vickers: | 1870HV |
Bending Strength: | 780MPa |
Fracture Toughness: | 7.2MPa·m1/2 |
Thermal Expansion Coefficient: | 3.2 10-6/K |
Thermal Conductivity: | 25W/(m·K) |
● Ball Sizes/Grade :
Size (mm) | Φ0.8-180 |
Grade | Vdws | SPH | Vdwl | Ra |
G3 | 0.05-0.08 | ≤0.08 | <0.13 | 0.01 |
G5 | 0.08-0.13 | ≤0.13 | <0.25 | 0.014 |
G10 | 0.15-0.25 | ≤0.25 | <0.5 | 0.02 |
G16 | 0.2-0.4 | ≤0.4 | <0.8 | <0.025 |
G20 | 0.3-0.5 | ≤0.5 | <1 | <0.032 |
G100 | 0.4-0.7 | 0.4-0.7 | <1.4 | <0.0105 |
Factory equipment
Exhibition & Partner
Case
Ship to South Korea
Ship to Spain
FAQ
1. What sizes and tolerances are available?
Diameter range: 0.5mm to 50mm (custom sizes possible).
Sphericity: As low as 0.1µm (Grade 5 for ultra-precision bearings).
Surface finish: Ra < 0.02µm (mirror polish for low friction).
2. Are silicon nitride balls FDA-approved for medical use?
Yes! Si3N4 is biocompatible (ISO 6474-1) and used in spinal implants, dental devices, and joint
replacements due to its antibacterial properties.
3. How do I choose the right Si3N4 balls for my application?
Consider:
Load & speed requirements (dynamic/static stress).
Temperature range (Si3N4 excels in high heat).
Chemical exposure (resistant to most acids/alkalis).
Electrical insulation needs (non-conductive).
