South Source Core can provide various custom ceramic to glass to metal hermetic seals, including seals providing power or transmitting signals in all sealed containers. The seals produced by us can mainly satisfy the requirements on air tightness, resistance to pressure and insulativity.
The ceramic to glass to metal hermetic seals are mainly applied in sealed containers as power input accessory for motor and some other parts requiring power. They can also be used for signal transmission under high pressure and extreme temperature in the sealed container. The ceramic to glass to metal hermetic seal features good air tightness, good insulation, good resistance to high pressure, good resistance to extreme temperature and some other advantages. Because of the additional ceramic insulator in the products, the glass can be better protected from pollution and damage. The overall creep-age distance of the product can be increased so that it will have better electrical property. The normal applications are ceramic hermetic terminals on the high voltage motor compressor of which the applied voltage can be up to 800V and hermetic terminals on the automobile air-conditioner compressor etc.
South Source Core can design proper products for our customers according to the specific requirements of them such as magnitude of the conduction current, magnitude of applied voltage, application environment, installation size etc.
The materials adopted to produce ceramic to glass to metal hermetic seals are usually decided according to the custom requirements of our customers. The expansion factors of the selected ceramic and glass and metal materials are carefully matched so that there will not be performance degradation of the metal material after sintering. The metal still features the following advantages: good elasticity, plasticity, rigidity, aging sensitivity, intensity, hardness, impact toughness, fatigue strength and fracture toughness etc.
Ceramic material: alumina ceramics (99%)
Glass material: high temperature and superior glass insulator from U.S.A and Japan;
Metal material: carbon steel, stainless steel, Kovar alloy, 52 alloy, 4J28.
The ceramic to glass to metal hermetic seals are mainly produced by compression seals technique. The expansion factor of ceramic, glass and metal are not the same, so the contraction of the metal is larger than that of ceramic and glass when cooling down during sealing in. So there will be compressive stress on ceramic and glass from metal. Thus, the sealing in can be accomplished. The seals produced by this process feature good air tightness and electrical property.
The surface treatment of ceramic to glass to metal hermetic seals adopts advanced electroless Ni plating process. The produced seals feature salt fog resistance which is over 48H. And there will be no peeling of plating during bending of the seals, so the glass will not be polluted. And the electrical property is quite good. The surface can also be treated by electroless silver or gold plating according to customers’ requirements.