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Resistivity of Aluminum Oxide

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Bibliographic Entry Result
(w/surrounding text)
Standardized
Result
Aluminum Oxide, Al2O3. Accuratus. 19 May 2006.
94% Aluminum Oxide
Volume Resistivity ohm·cm >1014
96% Aluminum Oxide
Volume Resistivity ohm·cm >1014
99.5% Aluminum Oxide
Volume Resistivity ohm·cm >1014
1 x 1014 Ω·cm
Material: Aluminum Oxide (Al2O3), Bulk. MEMS and Nanotechnology Clearinghouse. 19 May 2006. [see table below] 2 x 104 to 2 x 1011 Ω·m
Alumina (Al2O3) - Material Information. Goodfellow. 19 May 2006.
Electrical Properties
Volume resistivity @25C (Ohmcm) >1014
1 x 1014 Ω·cm
Alumina (Al2O3). AZoM. 19 May 2006. Resistivity at 20 ℃ (ohm.cm) >1014 1 x 1014 Ω·cm
Alumina, 99.9% Al2O3. Matweb Material Property Data. 19 May 2006.
Electrical Properties
Electrical Resistivity 1e+014 ohm-cm  
Electrical Resistivity 2.5e+006 ohm-cm at 900 ℃
2.5 x 106 to 1 x 1014 Ω·cm

Aluminum oxide, also known as alumina, is one of the most commonly used materials in engineering ceramics. Since minerals containing alumina include about 15% of the earth's crust, it is abundant and pretty much inexhaustible. With the addition of its affordable and cost effective price, aluminum oxide is a very popular material. It is also insoluble in water and has great resistance against weathering and strong acid. Alumina has an electrical resistivity of about 1x1014 Ω ·cm. It has good thermal conductivity and can reduce thermal shock resistance. Alumina is very useful in that it is available in a variety of purity ranges from 94% to 99.9%. It is usually white, but is sometimes pink (88% alumina) and brown (96% alumina). The composition of aluminum oxide can be easily changed to enhance certain desirable material characteristics such as the hardness or color. It also has excellent size and shape capability, which is advantageous for engineering production.

Aluminum oxide is an electrically insulating material with high resistivity that increases with purity With its high corrosion resistance, it does not wear easily, even against strong acid. Since aluminum oxide covers all aluminum metal, it is responsible for the metal's resistance to weathering. A thin layer of alumina will form on any exposed aluminum surface and protects it from further oxidation. Diamond tools are needed to machine or grind alumina Thus, this material is typically used for high temperature electrical insulators, high voltage insulators, electronic substrates, thermometry sensors, and grinding media. It is also used for gas laser tubes, furnace liner tubes, abrasion resistant tube, elbow liners, laboratory instrument tubes and sample holders. It is an excellent material for the use of engineers and scientists.

Property Value Conditions Reference
Electrical resistivity 2e+11 Ω*m Ceramic,at temp = 100 C CRC Materials Science and Engineering Handbook, p.565
Electrical resistivity 2e+11 Ω*m Ceramic,at temp = 100 C CRC Materials Science and Engineering Handbook, p.565
Electrical resistivity 1e+11 Ω*m Ceramic,at temp = 300 C CRC Materials Science and Engineering Handbook, p.565
Electrical resistivity 6.3e+08 Ω*m Ceramic,at temp = 500 C CRC Materials Science and Engineering Handbook, p.565
Electrical resistivity 5e+06 Ω*m Ceramic,at temp = 700 C CRC Materials Science and Engineering Handbook, p.565
Electrical resistivity 20000 Ω*m Ceramic,at temp = 1000 C CRC Materials Science and Engineering Handbook, p.565

Eunice Huang -- 2006