The nickel chromium alloy for electrical resistance heating has higher resistivity, great resistance to surface oxidation and excellent strength at high temperature as well as superior processability and weldability. For long time use, this nickel chromium alloy is hard to deform and has small elongation. In addition, it features high radiant emittance, strong corrosion resistance, nonmagnetic property and long service life.
In the family of this high resistance material, the Cr20Ni80 alloy boasts more superior comprehensive properties. It is the preferred alloy for high quality electrical heating element and widely used in metallurgy, household appliances and machinery manufacturing industry for heating elements and in electric appliance industry for resistance materials.
Since made from rare nickels, the nickel chromium alloy for electrical resistance heating comes with higher price than iron-chromium-aluminum alloy but lower service temperatures.Technical Parameters of Electrical Resistance Nickel Alloy
|Main chemical composition (％)||Ni||—||—||55.0~61.0||34.0~37.0||30.0~34.0|
|Maximum service temperature (℃)||1200||1250||1150||1100||1100|
|Average melting point (℃)||1400||1380||1390||1390||1390|
|Resistivity (μΩ.m,20 ℃)||1.09||1.18||1.12||1.0||1.04|
|Specific heat (J/g. ℃)||0.440||0.461||0.494||0.500||0.500|
|Heat conductivity coefficient (KJ/m.h.℃)||60.3||45.2||45.2||43.8||43.8|
|Linear expansion coefficient (α×10-6/℃)||18.0||17.0||17.0||19.0||19.0|