Mica Insulation Material
Mica is a kind of rock forming mineral, usually in a plate like, flaky, and columnar crystalline form of a false six square or a diamond. Because of its high temperature resistance, gloss, physical and chemical properties of stability, good insulation, flexibility and toughness, the insulation and heat resistance of mica are used in industry, as well as the acid and alkali resistance, compressive strength and exfoliation of insulating material for electrical equipment. Besides electrical insulation, it is also used in building materials industry, fire fighting industry, fire extinguishing agent, welding rod, plastic, paper making, asphalt paper, rubber, pearlescent pigment and other chemical industries.
The color characteristics of mica are usually used to characterize the insulation properties of mica.The industrial mica is generally good for light colored muscovite, the second of gold mica, and the worst insulation of black mica. The elastic coefficient of Muscovite is 15346 – 21760bar, and the gold mica is 14500 – 19480bar. When using mica as insulating material, it has strict requirements for its elasticity. Mica and mica powder can be processed into mica paper, and can also replace mica sheet to make all kinds of low cost and uniform insulation materials.
Mica insulation performance is the most important factor determining its industrial value. Mica insulation performance is determined by the electrical properties of mica. The electrical properties of mica are determined by testing breakdown voltage and breakdown strength. According to the test results of mica in various mining areas in China, when the mica thickness is 0.015mm, the average breakdown voltage is 2 – 5.7kV, and the breakdown strength is 133 – 407kV/mm.