Application background and overview of mica
Mica is a natural aluminosilicate mineral that can be peeled into soft and elastic flakes with a thickness of 0.01~0.03mm. It has high electrical insulation strength, good heat resistance, corrosion resistance and corona resistance. Commonly used in electrical engineering are muscovite (K2O·3Al2O3·6SiO2·2H2O) and phlogopite (K2O·6MgO·Al2O3·6SiO2·2H2O). The electrical insulation properties of muscovite are better than those of phlogopite, while the heat resistance of phlogopite is better than that of phlogopite. In addition to natural mica, there is also synthetic fluorphlogopite. Its composition is similar to phlogopite, except that fluorine is used instead of hydroxyl groups. It is made of Al2O3, SiO2, MgO, K2O, K2SiF6 and other raw materials at a temperature of about 1450°C. After melting, it is crystallized by slow cooling. Synthetic mica does not contain crystal water and has high purity. Its heat resistance, thermal shock resistance and electrical insulation properties are better than natural mica, but the price is higher.
Applications of mica
The reserves of high-quality natural mica are small and the loss rate during processing is high, thus promoting the development of powder mica technology. Powder mica is made by calcining natural mica fragments at 750 to 800°C, and then undergoing acid treatment, pulping, papermaking and other trifluoromethoxypyridine processes, or by pulverizing natural mica with high-pressure water, washing with water, and papermaking. process etc. Pink mica not only has uniform thickness and good performance, but also greatly improves the utilization rate of mica mineral materials and reduces costs.
Mica sheets can be directly used as insulation materials, but more often, mica sheets or powdered mica are used together with adhesives and reinforcing materials to make various mica products, including mica tapes, liners or commutators for motor insulation. Mica plates for appliances, mica foil for magnetic pole insulation, etc. In addition, there is also mica glass made from mica powder and low softening temperature boro-lead glass through hot melting, molding, and molding. It can be used as arc-resistant and high-temperature-resistant insulating materials for high-voltage electrical appliances.
A composite insulated conductive rod for motors, which includes a metal conductive rod and a composite insulating layer covering the metal conductive rod. The composite insulating layer is composed of a mica foil layer, an electrical film layer and a glued glass cloth layer; it uses The technical solution consists of a mica barium carbonate foil layer, an electrical film layer and a glued glass cloth layer to form a composite insulation layer covering a metal conductive rod. It overcomes the problems caused by the use of plastic insulation or laminated insulation in existing insulated conductive rods for motors. Defects that affect the mechanical strength, aging resistance and service life of the product; it is widely suitable for use on AC and DC motors and collector rings of AC motors, and is especially suitable for wind turbines and implementations that require high operational reliability and long service life. Motor products for special tasks and purposes.
