View source for Manganin

{{this|an alloy|the antimicrobial peptides|magainin}}
{{Infobox material
| name = Manganin
| image = 1900 Reichenstalt Pattern Resistor.jpg
| image_size = 
| alt = 
| caption = A manganin resistor made in 1900 at the [[Bushy House]] physics laboratory.
| type = Copper-manganese alloy 
| density = {{val|8.4|u=g/cm3}} 
| flammability = 
| limiting_oxygen_index = 
| water_absorption_eq = 
| water_absorption_24h = 
| radiation_resistance = 
| uv_resistance = 
| youngs_modulus = 
| tensile_strength = 300–600 MPa
| elongation = <50%
| compressive_strength = 
| poissons_ratio = 
| hardness_rockwell = 
| izod_impact_strength = 107 J/m
| notch_test = 
| abrasive_resistance_note = 
| abrasive_resistance = 
| coeff_friction = 
| speed_of_sound = 
| melting_point = 1020 °C
| glass_transition = 
| heat_deflection_temp_note = 
| heat_deflection_temp = 
| vicat_note = 
| vicat = 
| vicat_a = 
| vicat_b = 
| upper_working_temp = 
| lower_working_temp = 
| heat_transfer_coeff = 
| thermal_conductivity_note = at {{val|23|u=degC}}
| thermal_conductivity = 22 [[Watt|W]]/([[Metre|m]]·[[Kelvin|K]])
| thermal_diffusivity_note = 
| thermal_diffusivity = 
| linear_expansion = {{val|14|-|19|e=-6|u=K<sup>−1</sup>}}
| specific_heat = 0.097 cals/gm
| dielectric_constant_note = 
| dielectric_constant = 
| permittivity = 
| relative_permeability_note = 
| relative_permeability = 
| permeability_note = 
| permeability = 
| dielectric strength = 
| dissipation_factor_note = 
| dissipation_factor = 
| surface_resistivity = 
| volume_resistivity = 43–48 μΩ⋅cm
| chem_res_acid_c = 
| chem_res_acid_d = 
| chem_res_alcohol = 
| chem_res_alkali = 
| chem_res_aromatic = 
| chem_res_grease_oil = 
| chem_res_haloalkane = 
| chem_res_halogen = 
| chem_res_ketone = 
| gas_perm_temp = {{val|20|u=degC}}
| gas_perm_N = 
| gas_perm_O = 
| gas_perm_CO2 = 
| gas_perm_H2O = 
| price = 
| footnotes = Source<ref name="properties">{{cite web|title=Manganin 230 Shunt Wire|url=http://www.calfinewire.com/datasheets/100115-manganin230shunt.html|website=California Fine Wire Co|accessdate=13 January 2018|language=en}}</ref>
}}

'''Manganin''' is a [[trademark]]ed name for an [[alloy]] of typically 84.2% [[copper]], 12.1% [[manganese]], and 3.7% [[nickel]]. It was first developed by [[Edward Weston (chemist)|Edward Weston]] in 1892, improving upon his [[Constantan]] (1887).

Manganin [[Foil (chemistry)|foil]] and [[wire]] is used in the manufacture of [[resistor]]s, particularly [[Shunt (electrical)#Use in current measuring|ammeter shunts]], because of its virtually zero [[temperature coefficient of resistance]] value<ref name=":0">{{Cite web|url=http://www.goodfellow.com/catalogue/GFCat2H.php?ewd_token=09GRBJvlw6lL5lDbZC1qWnos3v9ad5&n=kCvbg9HE4EQs6Xg56ttKPuupoT1SdP&ewd_urlNo=GFCat2L3&Head=CU06|title=Goodfellow Technical Information Manganin® - Resistance Alloy|website=www.goodfellow.com|access-date=2016-09-11}}</ref> and long term stability. Several Manganin resistors served as the legal standard for the [[Ohm (unit)|ohm]] in the United States from 1901 to 1990.<ref>{{Cite web |url=https://nvlpubs.nist.gov/nistpubs/sp958-lide/063-065.pdf |title=Stability of Double-Walled Manganin Resistors |access-date=2007-04-30 |archive-url=https://web.archive.org/web/20240930055258/https://nvlpubs.nist.gov/nistpubs/sp958-lide/063-065.pdf |archive-date=2024-09-30 |url-status=live}}</ref>  Manganin wire is also used as an electrical conductor in [[Cryogenics|cryogenic systems]], minimizing heat transfer between points which need electrical connections.

Manganin is also used in gauges for studies of [[High pressure|high-pressure]] [[shock waves]] (such as those generated from the detonation of [[Explosive material|explosives]]) because it has low [[Strain (materials science)|strain]] sensitivity but high [[Fluid statics#Hydrostatic pressure|hydrostatic pressure]] sensitivity.<ref>{{cite web |title=Special Use Sensors - Manganin Pressure Sensor |url=http://web.sensor-ic.com:8000/ZLXIAZAI/VISHAY/thumb_2011032859967085.pdf |website=web.sensor-ic.com |publisher=Vishay |access-date=15 April 2023 }}{{Dead link|date=April 2024 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

== History ==
{{Expand section|date=January 2011}}

In 1887 Edward Weston discovered that metals can have a negative temperature coefficient of resistance, inventing what he called his "Alloy No. 2." 
It was produced in Germany where it was renamed "[[Constantan]]".<ref>{{Cite book|url=https://archive.org/details/chronologicalhis00natirich|title=A chronological history of electrical development from 600 B.C.|last=National Electrical Manufacturers Association|date=1946 |publisher=New York, N.Y., National Electrical Manufacturers Association}}</ref> In 1888 he patented<ref>{{US patent|381304A}}</ref> "an alloy containing from 65 to 70 parts of copper, 25 to 30 parts of [[Ferromanganese|ferro-manganese]], and 2.5 to 10 parts of nickel" which had a nearly constant resistivity.

Manganin wire as we know it was developed by Weston's assistant [[John Forrest Kelly]].<ref>{{Cite journal |last=Fessenden |first=Reginald A. |date=1893-07-21 |title=Electrical Notes |url=https://books.google.com/books?id=wdlCTzYLf2kC&pg=RA1-PA36 |journal=Science |language=en |volume=ns-22 |issue=546 |pages=35–36 |doi=10.1126/science.ns-22.546.35 |issn=0036-8075|url-access=subscription }}</ref> In May 1893, Weston received a patent{{Source?|date=October 2024}} for the material and its use for resistors. While Manganin represented a significant advance in technology -- the material was a conductive metal with constant resistance over a wide range of working temperatures, Weston did not receive wide recognition at the time.<ref>{{Cite book
  |url=https://archive.org/details/measureforgreatn001419mbp
  |title=A Measure for Greatness; A Short Biography of Edward Weston
  |first=David O.  |last=Woodbury
  |year=1949  
  |publisher=McGraw-Hill |location=New York, Toronto, London 
}}</ref>

== Properties ==

=== Cu86/Mn12/Ni2 ===
{{Cleanup-layout|date=November 2012 }}
Electrical Properties
* Temperature coefficient: {{val|1.5|e=-5|u= K<sup>−1</sup>}}
Mechanical Properties
* Modulus of elasticity: 124–159 GPa
* Maximum use temperature in air: 300 °C

{| class="wikitable" style="text-align: center"
|+ Cu84/Mn12/Ni4<ref>{{cite book|title=CRC Handbook 27th ed.|date=Feb 1943|page=1875}}</ref>
|-
! Temperature [°C]
! coefficient of resistivity
|-
| {{fsp}}12   
| +.000006
|-
| {{fsp}}25   
| {{fsp}}.000000
|-
| 100  
| −.000042
|-
| 250  
| −.000052
|-
| 475   
| {{fsp}}.000000
|-
| 500   
| +.00011{{fsp}}
|}

{| class="wikitable" style="text-align: center"
|+ Resistance of Wires at {{val|20|u=degC}}<ref>{{cite book|title=CRC Handbook 27th ed.|date=Feb 1943|page=2485}}</ref> 
|-
! [[AWG]]
! ohms per cm
! ohms per ft
|-
| 10 
| .000836 
| {{fsp}}0.0255
|-
| 12
| .00133{{fsp}}
| {{fsp}}0.0405
|-
| 14
| .00211{{fsp}}
| {{fsp}}0.0644
|-
| 16
| .00336{{fsp}}
| {{fsp}}0.102{{fsp}}
|-
| 18
| .00535{{fsp}}
| {{fsp}}0.163{{fsp}}
|-
| 20
| .00850{{fsp}}
| {{fsp}}0.259{{fsp}}
|-
| 22
| .0135{{fsp|2}}
| {{fsp}}0.412{{fsp}}
|-
| 24
| .0215{{fsp|2}}
| {{fsp}}0.655{{fsp}}
|-
| 26
| .0342{{fsp|2}}
| {{fsp}}1.04{{fsp|2}}
|-
| 27
| .0431{{fsp|2}}
| {{fsp}}1.31{{fsp|2}}
|-
| 28
| .0543{{fsp|2}}
| {{fsp}}1.66{{fsp|2}}
|-
| 30 
| .0864{{fsp|2}}
| {{fsp}}2.63{{fsp|2}}
|-
| 32
| .137{{fsp|3}}
| {{fsp}}4.19{{fsp|2}}
|-
| 34
| .218{{fsp|3}}
| {{fsp}}6.66{{fsp|2}}
|-
| 36
| .347{{fsp|3}}
| 10.6{{fsp|3}}
|-
| 40
| .878{{fsp|3}}
| 26.8{{fsp|3}}
|}

== See also ==

* [[List of named alloys]]

== References ==
{{reflist}}

== External links ==
* [https://archive.today/20071130230852/http://www.isabellenhuette.de/en/research-development/ Isabellenhütte - 1889 Manganin]

[[Category:Copper alloys]]
[[Category:Nickel alloys]]