Scope of the bimetallic material is very extensive: oil and gas, nuclear energy, coinage, utensils, etc.
Bimetals manufactures a wide range of methods: electroplating, thermal spraying, welding and others.
Called bimetal composite material inwherein one metal is usually cheaper, covered with another, more expensive with the best performance. If the amount of metal in the composite is 3, it is called trimetallom. The composition of the metal is not more applicable.
Application of bimetals
Anti-corrosion coatings. Everywhere where you have to cover the weak corrosive metal, used copper, nickel, silver, or other coating with superior performance characteristics. This bimetal actively used to make corrosion-resistant equipment of oil and gas and atomnoenergeticheskogo equipment, glassware, kitchen utensils and clad coins.
Temperature-sensitive elements. By selecting a metal with different coefficients of thermal expansion is possible to obtain the bimetal, which will deform in the direction of metal with a lower coefficient of thermal expansion.
Anti-friction coating. Such bimetal simultaneously be inexpensive and resistant to abrasion.
Methods for manufacturing bimetal
Galvanic. With the passage of electricity through a solution of the Faraday processes occur, for example, metal is deposited. By selecting certain electrolyte composition, solution temperature, solution composition, achieve deposition on the surface of the metal coating with the desired properties. For example, the most simple electrolyte to precipitate the copper shiny coating should contain copper sulfate, sulfuric acid and gelatin. The process is carried out at room temperature at a current of 1-5 A / dm2.
Gas thermal spraying. Metal is transferred in dispersed state and a gas or plasma stream is fed to the substrate, which condenses.
Surfacing electric or plasma heating.
Immersion into the melt.
Explosive Welding. Two laminated metal sheet positioned parallel. On the one hand carried out a controlled explosion that causes the two sheets in close contact. Welding takes place by simultaneous deformation.
The main drawback of bimetal - itelectrochemical corrosion, which occurs at the ends, where both metals are simultaneously available to the external environment. But, if the potential of the electrode coating is less than the base metal, the coating provides sacrificial protection even.