Alumina ( Al2O3 ) – Physical, Mechanical, Thermal, Electrical and Chemical Properties – Supplier Data by Ceramaret

AZoM - metals, ceramics, polymers and composites - Ceramaret logo

Topics Covered

Background

Physical Properties

Mechanical Properties at 20°C

Thermal Properties

Electrical Properties

Chemical Properties

Background

Alumina, Al2O3, is available from Ceramaret with a purity of up to 99.9%. It is a polycrystalline material with a grain size of 1 to 5 microns, an average density of 3.95 g/cm³ and a hardness of about 2000 Vickers.

AZoM - Alumina from Ceramaret

Physical Properties

Property

Value

Atomic composition

>99%

Crystalline structure

Corundum

Grain size (microns)

1-5

Density (g/cm3)

3.95

Water absorption (%)

0

Mechanical Properties at 20°C

Property

Value

Vickers hardness (Hv 500g)

1800-2000

Tensile strength (N/mm2)

200-250

Bending strength (N/mm2)

200-600

Compressive strength (N/mm2)

1900-2000

Young’s modulus (N/mm2)

3.8x105

Poisson’s ratio

0.25-0.30

Fracture toughness KIC -½ (MPa.m)

4-5

Thermal Properties

Property

Value

Dilation co-efficient (20-2000°C) (°C-1)

8.4x10-6

Specific heat 100°C (J/kg.K)

930

Thermal conductivity at 20°C (W/m.K)

40

Thermal shock resistance (°C)

200

Electrical Properties

Property

Value

Resistivity at 20°C (ohm.cm)

>1014

Dielectric constant at 20°C and 1GHz

9.5

Dielectric rigidity at 50Hz (KV/mm)

30

Chemical Properties

Chemicals

Concentration

Temperature

Time

Rating

HCl

35%

Boiling

30 min

A

HNO3

70%

Boiling

30 min

A

H2SO4

98%

Boiling

30 min

A

H3PO4

90%

Boiling

30 min

B

HF

60%

20

24 hr

C

KOH solution

10%

80

7 day

A

KOH boiling

 

500

24 hr

C

NaOH boiling

 

500

24 hr

B

Na2CO3 boiling

 

900

24 hr

B

Na2SO4 boiling

 

1000

24 hr

A

KF boiling

 

90

4 hr

D

A: no corrosion observed

B: slightly corroded

C: middle degree of corrosion

D: heavily corroded

 

Note: The values quoted are typical. Ceramic property values can vary with the method of manufacture.

 

Source: Ceramaret SA

 

For more information on this source please visit Ceramaret SA

 

Date Added: May 2, 2006 | Updated: Jun 11, 2013
Ask A Question

Do you have a question you'd like to ask regarding this article?

Leave your feedback
Submit