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PPC CERAMIC® (Al₂O₃)

Ceramic (Alumina Al₂O₃) Flat Washers - ISO 7089

In stock - 31 items available
SKU: CERWAM3
Al₂O₃ Datasheet
$9.83

Alumina ceramic metric flat washers provide electrical insulation and a durable bearing surface for metric screws and bolts. Made from aluminum oxide (Al₂O₃), these nonmetallic washers combine high hardness, heat resistance, and resistance to wear and corrosion for demanding industrial assemblies.

Their flat design helps distribute fastening loads while separating mating surfaces. Ceramic insulating washers are a practical choice for electrical equipment, electronics, and applications where metal washers may introduce unwanted electrical conductivity.

Key Features

  • Electrical insulation: Helps isolate conductive components.
  • Heat resistance: Alumina offers thermal stability for elevated-temperature applications.
  • Wear and corrosion resistance: Supports use in demanding operating environments.
  • Metric sizing: For use with compatible metric screws and bolts.
  • Flat washer design: Provides a bearing surface beneath a fastener head or nut.
  • Type Washers
  • SKU CERWAM3
  • Material Ceramic AL2O3
  • Color
    • Natural
  • Measurement System Metric
  • ISO Standard ISO 7089
  • DIN Standard DIN 125A

Material: Ceramic (99.5% Alumina Al₂O₃)

Maximum Duty Temperature: 2732ºF

Flammability: Noncombustible

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Flat Washer Dimension Table (ISO7089/DIN125A)
M Size Inside Diameter (mm) Outside Diameter (mm) Thickness (mm)
M3 3.2 7.0 0.5
M4 4.3 9.0 0.8
M5 5.3 10.0 1.0
M6 6.4 12.5 1.6
M7 7.4 14.0 1.6
M8 8.4 17.0 1.6
M10 10.5 21.0 2.0
M12 13.0 24.0 2.5
M14 15.0 28.0 2.5
M16 17.0 30.0 3.0
M18 19.0 34.0 3.0
M20 21.0 37.0 3.0

Ceramic (99.5% Alumina Al₂O₃)

Key Properties & Applications
Properties Applications

- Extremely High Hardness
- Extremely High Temperature Operation Capability
- Excellent Creep Resistance
- Outstanding Resistance to Acids & Alkalis

- High Temperature Furnaces and Kilns
- Vacuum & Ultra-High Vacuum Equipment
- Laboratory & Analytical Equipment
- Aerospace & Defence Systems

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