Machining Examples

Alumina (Al2O3) – Custom Machined Parts

Alumina, also known as Aluminum Oxide, is the most popular ceramic material. It is a relatively low cost ceramic material with good machinability and has a very wide range of applications.

Alumina Properties

Property Vickers Hardness (GPa) Fracture Toughness (MPa· m1/2) Max Use Temperature(℃) Coefficient of Thermal Expansion(×10-⁶/℃) Thermal Conductivity
Thermal Shock Resistance(℃) Dielectric Strength(kv/mm) Chemical Resistance
Chemical Formula & Purity
18 4 1,300
(in air)
30 200 >10 Good
18 4 1,500
(in air)
33 200 >10 Good

※For more information, see Material Guide

Alumina – Key Properties & Popular Applications

Key Properties Applications
High Hardness Alumina has high wear resistance due to its high hardness. It also has good resistance to breaking and cracking due to its high fracture toughness and flexural strength. ■Precision parts and components
■Jigs & fixtures
■Wear-resistant parts such as nozzles, pumps, valves and thread/wire guides.
■Heat insulation parts
■Heat spreaders
■Crucibles & crucible liners
■Electric insulation parts
■High temperature electrical insulators
■Parts used in reactive gas environments such as gas distributors / showerheads, and chamber liners
■Parts for plasma chambers
■Cylinders and pistons
High Temperature Resistance & Low Thermal Expansion Alumina has excellent thermal stability up to 1300 ℃. Because it is an oxide ceramic material, it can be used in oxidizing atmospheres at high temperatures.
Its low coefficient of thermal expansion makes it ideal for high temperature applications where dimensional stability is required.
High Dielectric Strength Alumina has excellent dielectric properties.
Good Chemical Resistance Alumina has excellent corrosion resistance. It resists attack by most gases including acid gases. It is also plasma resistant.
Good Machinability Alumina has a good machinability compared to other engineering ceramics. Because it has been a popular ceramic material, we have extensive experience in machining it. Machining to micron accuracy is possible.

Available Sizes and Machining Capability

Availability Sizes(mm) Machining Capability Sizes(mm)
Plate 500×800×30 Hole diameter Φ0.1~
Rod Φ100×300 Hole depth ~300
Groove width 0.05 or more Max. hole number 3,000 (approx.)
Max. step height ~70 Thread size M1.6~

Ceramics List

  • Alumina(Al₂O₃)

    Excellent electrical insulation properties , High temperature resistance , Plasma resistance , High hardness , Wear resistance

  • Aluminum nitride(AlN)

    High thermal conductivity , High temperature resistance , Low thermal expansion , Excellent electrical insulation properties , Plasma resistant , Corrosion resistant

  • Zirconia(ZrO2)

    High fracture toughness , Low thermal conductivity , Wear resistant

  • Silicon carbide(SiC)

    High hardness , High thermal conductivity , High mechanical strength , Corrosion resistant

  • Silicon Nitride (Si3N4)

    High fracture toughness , Low thermal expansion , Wear resistant , Good thermal shock resistance

  • Machinable Ceramics

    Excellent electrical insulation properties , High machinability , High temperature resistance

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