Alumina Ceramic offers superior insulation properties for electricity along with great wear and tear resistance and high hardness but has a comparatively lower strength and the fracture toughness. It is the most mature form of the engineering ceramics. Most of the Alumina Ceramics is generally white. Some of them might also be pink which has about eighty-eight percent of alumina or brown that has approximately ninety six percent of alumina. The colour of the ceramic comes from the impurities in the raw materials or from the sintering additives.
Alumina ceramics that have superior purity are best for the environment where in the resistance to corrosive substances or wear and tear is required. These ceramics are also used in areas where the temperatures are very high and resistance to it is required as this ceramic is known to have a great thermal stability. For the alumina wear parts, the alumina ceramic is the best material as the ability to resist heat and wear and tear makes the ceramic ideal for manufacturing of components that are wear resistant.
Alumina is known to be an excellent electrical insulator having resistance to very high electricity. The great thing about alumina is the fact that the resistance to electricity increases with the purity of it. The more pure alumina is, the higher the resistance would be. Alumina also has a very high melting point and high hardness. The mechanical strength starts to reduce when the temperature goes beyond 1000 C. Hence, the resistance to thermal shock reduces because of the huge coefficient of the thermal expansion.
The high resistance to corrosion in alumina is derived from a great chemical stability. Alumina is slightly soluble in alkaline and strong acid solutions and absolutely insoluble in water. The alumina with superior purity is the main choice for the components in a wide array of industrial applications because of its ability to resist chemical corrosion. It has been proved that the alumina has high resistance to the corrosion caused by chemicals because of the lower solubility in chemicals.
The alumina ceramic is blended with the additives that work on enhancing its properties. A great variety of shapes and sizes of the components can be produced by using several varieties of the processing methods of ceramic like net shape or machining. High thermal conductivity, high resistance to heat, great insulator of electricity and high resistance to corrosion are a few factors why alumina ceramics is favoured amongst many manufacturers.