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A laminate of two dissimilar metals, with different coefficients of thermal expansion, bonded together.



a metallic material consisting of two layers of heterogeneous metals or alloys (such as steel and aluminum, steel and niobium, aluminum and titanium, titanium and molybdenum). Bimetals are used to increase the strength or heat resistance of structures, to reduce their bulk while economizing on expensive or scarce materials, and to obtain materials with special characteristics when required. For example, in electrical and radio engineering, bimetals are widely used because the density of an alternating current is greater at the periphery of the conductor than at its core, and therefore it is sometimes expedient to coat the surface of a conductor made of cheaper material (steel or aluminum) with good conductive material (copper or silver). In instrument-making, the differences in temperature coefficients of expansion of the different metals in bimetallic plates are utilized. In machine-building, certain parts of machinery, such as bush bearings, are made of bimetals.

Bimetals are made primarily by simultaneous rolling or pressing of two slabs of different metals or alloys. The casting of a fusible metal onto a refractory one and the immersion of a refractory metal in a molten fusible one are also common. In electroplating, the layer of the more precious metal is applied electrolytically. The expensive and scarce harder alloys are applied to steel by electric heating (in the production of cutting tools, dies, and the like).

References in periodicals archive ?
The team also checked through experiments that the circuit breaker using the bimetal operated below AC 1 KV can be replaced by that made of the developed MIT electromagnetic switching technology.
Shivalik Bimetal Controls Ltd (SBCL) was incorporated in June 1984 by Mr.
The final bimetal was pbtained by explosion welding.
Greater part of produced in this country and in the world bimetal materials is represented by hotrolled double-layer corrosion-resistant sheets.
The valves are powered by a DURA-trol[R] solid bimetal thermostat, which is resistant to puncture and fatigue and cannot be damaged when temporarily exposed to excessive temperatures.
Seattle began prohibiting the disposal of paper and corrugated containers, aluminum and bimetal cans and bottles from commercial waste streams at the start of this year in an effort to reach a recycling goal of 60 percent.
Bimetal and carbide-tipped blades cut soft alloys quickly, but abrasive aluminum still takes a toll in reduced blade life and lost shop time, advises Jack Leonard, band saw specialist, Bahco North America, Inc.
To control the fluid temperature, a choice of bimetal switches with various settings, a PT 100 RTD or a 4 to 20 mA transmitter, are available for direct and cordless attachment to the printed board.
LLC, the company that developed SMI-98--a bimetal composite material similar to those being used in the aerospace industry.
a member of the Instrumentation Group in Asheville, North Carolina, has introduced a new line of bimetal dial thermometers.
The new company, to be capitalized at 500 million yen, will be owned 40% by Daido and 60% by Bimetal Bearings Ltd.
PDI's Prisma bimetal plate consists of a thermally sensitive polymer coating, with an infrared dye sensitive at 1064nm, applied to a copper-plated aluminum substrate.