Balco alloy
Encyclopedia
Balco is a nickel
-iron
alloy
with a thermal conductivity
similar to nickel but twice the resistivity
. It is used for making low cost resistance temperature sensors. It consists of 70% nickel and 30% iron.
Balco is Carpenter's brand name for this alloy consisting of 70% nickel and 30% iron. It is also sold by Harrison as "Hytemco". Its principal use is for RTDs (resistance temperature detectors). An RTD changes its electrical resistance as a predictable function of temperature, making it useful as a thermometer with electrical output. Balco has a temperature coefficient of resistance of .00518, nearly as high as that of pure nickel (.00672) but with much better linearity. It is also mechanically strong and fairly corrosion resistant.
Pure platinum is preferred for the most precise RTD elements in spite of its price and lower temperature coefficient (.00385). This is because of its long-term stability and repeatability.
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
-iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
with a thermal conductivity
Thermal conductivity
In physics, thermal conductivity, k, is the property of a material's ability to conduct heat. It appears primarily in Fourier's Law for heat conduction....
similar to nickel but twice the resistivity
Electrical resistance
The electrical resistance of an electrical element is the opposition to the passage of an electric current through that element; the inverse quantity is electrical conductance, the ease at which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical...
. It is used for making low cost resistance temperature sensors. It consists of 70% nickel and 30% iron.
Balco is Carpenter's brand name for this alloy consisting of 70% nickel and 30% iron. It is also sold by Harrison as "Hytemco". Its principal use is for RTDs (resistance temperature detectors). An RTD changes its electrical resistance as a predictable function of temperature, making it useful as a thermometer with electrical output. Balco has a temperature coefficient of resistance of .00518, nearly as high as that of pure nickel (.00672) but with much better linearity. It is also mechanically strong and fairly corrosion resistant.
Pure platinum is preferred for the most precise RTD elements in spite of its price and lower temperature coefficient (.00385). This is because of its long-term stability and repeatability.