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Bimetal refers to an object that is composed of two separate metals joined together. Instead of being a mixture of two or more metals, like alloys, bimetallic objects consist of layers of different metals. Trimetal and tetrametal refer to objects composed of three and four separate metals respectively. A bimetal bar is usually made of brass and iron.

Bimetallic strips and disks, which convert a temperature change into mechanical displacement,^[1] are the most recognized bimetallic objects due to their name. However, there are other common bimetallic objects. For example, tin cans consist of steel covered with tin.^[2] The tin prevents the can from rusting. To cut costs and prevent people from melting them down for their metal, coins are often composed of a cheap metal covered with a more expensive metal. For example, the United States penny was changed from 95% copper to 95% zinc, with a thin copper plating to retain its appearance. A common type of trimetallic object (before the all-aluminium can) was a tin-plated steel can with an aluminum lid with a pull tab. Making the lid out of aluminum allowed it to be pulled off by hand instead of using a can opener, but these cans proved difficult to recycle owing to their mix of metals.

Blades for bandsaws and reciprocating saws are often made with bimetal construction. The teeth, made of high-speed steel, are bonded (by various methods, for example, electron beam welding or laser beam welding) to the softer high-carbon steel base. Such construction makes for blades with a better combination of cutting speed and durability than shown by non-bimetal blades, because the advantages and disadvantages of each of the metals are applied in the best locations: the teeth are harder (and thus cut better), but therefore also brittler; meanwhile, the body area of the band is softer (which would make for poorer teeth), but also less brittle, and thus more resistant to cracking and breaking (which is desirable in the body area).

References

^ NASA. "Bimetal sensor for averaging temperature measurement of nonuniform temperature profiles" (PDF).
^ Gaurav Kr. Deshwal and Narender Raju Panjagari (2019). "Review on metal packaging: materials, forms, food applications, safety and recyclability". Journal of Food Science and Technology. 57 (7): 2377–2392. doi:10.1007/s13197-019-04172-z. PMC 7270472. PMID 32549588.

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+{{Short description|Object made of two different metals joined together}}
-{{Unreferenced|date=August 2010}}
-{{move to wiktionary}}
 '''Bimetal''' refers to an object that is composed of two separate [[metal]]s joined together. Instead of being a [[mixture]] of two or more metals, like [[alloy]]s, bimetallic objects consist of layers of different metals. Trimetal and tetrametal refer to objects composed of three and four separate metals respectively. A bimetal bar is usually made of brass and iron.
 [[File:Bimetallic stripe.svg|thumb|300px|Shows the principle of non-heated (left) and heated (right) bimetal]]
-[[Bimetallic strip]]s and disks, which convert a temperature change into mechanical displacement, are the most recognized bimetallic objects due to their name. However, there are other common bimetallic objects. For example, [[tin can]]s consist of [[steel]] covered with [[tin]]. The tin prevents the can from [[rust]]ing. To cut costs and prevent people from melting them down for their metal, [[coin]]s are often composed of a cheap metal covered with a more expensive metal. For example, the [[Cent (United States coin)|United States penny]] was changed from 95% [[copper]] to 95% [[zinc]], with a thin copper [[plating]] to retain its [[Cent (United States coin)#References|appearance]]. A common type of trimetallic object (before the all-aluminium can) was a tin-plated steel can with an [[aluminum]] lid with a pull tab. Making the lid out of aluminum allowed it to be pulled off by hand instead of using a [[can opener]], but these cans proved difficult to [[Recycling|recycle]] owing to their mix of metals.
+[[Bimetallic strip]]s and disks, which convert a temperature change into mechanical displacement,<ref>{{Cite web|title=Bimetal sensor for averaging temperature measurement of nonuniform temperature profiles|url=https://ntrs.nasa.gov/api/citations/19680006467/downloads/19680006467.pdf|author=NASA}}</ref> are the most recognized bimetallic objects due to their name. However, there are other common bimetallic objects. For example, [[tin can]]s consist of [[steel]] covered with [[tin]].<ref>{{Cite journal|title=Review on metal packaging: materials, forms, food applications, safety and recyclability|author=Gaurav Kr. Deshwal and Narender Raju Panjagari|journal=Journal of Food Science and Technology |year=2019 |volume=57 |issue=7 |pages=2377–2392 |doi=10.1007/s13197-019-04172-z |pmid=32549588 |pmc=7270472 }}</ref> The tin prevents the can from [[rust]]ing. To cut costs and prevent people from melting them down for their metal, [[coin]]s are often composed of a cheap metal covered with a more expensive metal. For example, the [[Cent (United States coin)|United States penny]] was changed from 95% [[copper]] to 95% [[zinc]], with a thin copper [[plating]] to retain its [[Cent (United States coin)#References|appearance]]. A common type of trimetallic object (before the all-aluminium can) was a tin-plated steel can with an [[aluminum]] lid with a pull tab. Making the lid out of aluminum allowed it to be pulled off by hand instead of using a [[can opener]], but these cans proved difficult to [[Recycling|recycle]] owing to their mix of metals.
-Blades for [[bandsaw]]s and [[reciprocating saw]]s are often made with bimetal construction. The teeth, made of [[high speed steel]], are bonded (by various methods, for example, [[electron beam welding]] or [[laser beam welding]]) to the high-strength carbon steel base. Such construction makes for blades with a better combination of cutting speed and durability than shown by non-bimetal blades, because the advantages and disadvantages of each of the metals are applied in the best locations: the teeth are [[hardness|harder]] (and thus cut better), but therefore also [[brittleness|brittler]]; meanwhile, the body area of the band is softer (which would make for poorer teeth), but also less brittle, and thus more resistant to cracking and breaking (which is desirable in the body area).
+Blades for [[bandsaw]]s and [[reciprocating saw]]s are often made with bimetal construction. The teeth, made of [[high-speed steel]], are bonded (by various methods, for example, [[electron beam welding]] or [[laser beam welding]]) to the softer high-carbon steel base. Such construction makes for blades with a better combination of cutting speed and durability than shown by non-bimetal blades, because the advantages and disadvantages of each of the metals are applied in the best locations: the teeth are [[hardness|harder]] (and thus cut better), but therefore also [[brittleness|brittler]]; meanwhile, the body area of the band is softer (which would make for poorer teeth), but also less brittle, and thus more resistant to cracking and breaking (which is desirable in the body area).
-== See also==
+== See also ==
 {{Commons cat|Bimetallic strips|Bimetallic strips}}
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 * [[Thermocouple]] (electric)
 * [[Copper-clad steel]]
+== References ==
+<references />
+== Further reading ==
+* [https://pubmed.ncbi.nlm.nih.gov/19334923/ Thermal imaging with tapping mode using a bimetal oscillator formed at the end of a cantilever ]
+* [https://matmatch.com/learn/material/bimetal Bimetal: Definition, Properties, and Applications]
+* [https://www.ibt.co.il/uploaded_files/documents/Kanthal_Thermostatic_Bimetal_U3743.pdf Kanthal Thermostatic Bimetal]
+* [https://www.emsclad.com/fileadmin/Data/Divisions/EMS/Header/Bimetal_Desingers_ Guide.pdf How Thermostatic Bimetal Works]
 {{Authority control}}
-[[Category:Bimetal]]
+[[Category:Bimetal| ]]
 [[Category:Metallurgy]]
 [[Category:Composite materials]]