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The Properties of Ceramic Screws

Physical Properties

Al2MO3(99.5% Alumina)
Specific Gravity 3.9 - 3.939
Flexural Strength(N/mm2) 360
Volume Resistivity(Ω・m) >1012
Thermal Conductivity(W/(m・K)) 32(20℃)
Linear Expansion Coefficient(K-1) 7.2×10-6(40 - 400℃)
Vickers Hardness(GPa) 15.5
Maximum Duty Temperature(℃)(GPa) 1500
  • Values in chart are for reference only. They are not guaranteed values.

Chemical Resistance of Ceramic Screws

Chemical Name Temperature Hour Effect
35% Hydrochloric Acid Boiling 30 minutes
70% Nitric Acid Boiling 30 minutes
98% Sulfuric Acid Boiling 30 minutes
90% Phosphoric Acid Boiling 30 minutes
60% Hydrofluoric Acid 20℃ 24 hours
10% Potassium Hydroxide 80℃ 7 Days
Potassium Hydroxide 500℃(Boiling) 24 hours
Sodium Hydroxide 500℃(Boiling) 24 hours
Sodium Carbonate 900℃(Boiling) 24 hours
Sodium Sulfate 1000℃(Boiling) 24 hours
Potassium Fluoride 90℃(Boiling) 4 hours ×
  • ◎:No Corrosion
  • 〇:Slight Corrosion
  • △:Moderate Corrosion
  • ×:Heavy Corrosion

  • When tightening ceramic screws, use a torque driver or torque wrench and do not exceed the torsional torque.The recommended torque is 50% of the torsional torque.
M Torsional Torque (N・m)
M3 0.04
M4 0.05
M5 0.10
M6 0.15
M8 0.30
M10 0.50
  • Values in chart are for reference only. They are not guaranteed values.

  • Heat resistance and chemical resistance change with performance conditions. Always carry out tests under performance conditions similar to actual conditions in advance.
  • Ceramic screws may be damaged by impact. Take care when handling these screws.
  • Also, ceramics screws with special specifications such as ventilation holes, dimensions, shapes, and cleanroom washing are available. Please contact us for details.
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