high temperature ni70cr30 cr20ni80 nicr nichrome resistance wire
Heat resistance wire is a type of high resistance electrical wire.
The wire resists the flow of electricity, and converts the
electrical energy into heat.
Nichrome, a non-magnetic alloy of nickel and chromium, is commonly
used to make resistance wire because it has a high resistivity and
resistance to oxidation at high temperatures. When used as a
heating element, resistance wire is usually wound into coils.
The high nickel content, in combination with the high chromium
content let the scaling temperature can reach to 1250ºC
Chrome Nickel wire was shaped by means of high speed automatic
cooling machine of which the power capacity is controlled by
computer, they are available as wire and ribbon(strip).
nichrome wire resistance Product forms and size range
| Nichrome Alloy Grade | Cr20Ni80,Cr20Ni30,Cr15Ni60,Cr20Ni35,Cr20Ni40 |
| Form | Round wire,Flat wire,Strip,Bar,Spring shaped wire, Wave shaped
strip,Radiant tube heater |
| Size | Wire: 0.030mm-10mm Ribbon: 0.05*0.2mm-2.0*6.0mm
Strip: 0.5*5.0mm-5.0*250mm furnance spring wire according to customers requirement
|
nichrome wire resistance Features and advantages
1)The highest working temperature up to 1200 degree.
2)higher strength than iron chromium aluminum under high
temperature
3)not easy to deform under high temperature
4)good plasticity
5)easy to repair,
6)high emissivity,
7)Non-magnetic
8)strong corrosion resistance,
9)long service life
Uses of nichrome wire
Chrome nickel wire resistance is widely used for making electric
heating elements in home appliances and industrial
furnaces.,various electrical resistors and locomotive braking
resistor, infrared equipment, liquefied gas infrared heat-resisting
net, different kinds of igniting and radiating electrodes and
voltage-regulating resistors for motors and so on in Metallurgical
machinery
nichrome wire resistance Main characteristics
| Type | Cr20Ni80 | Cr15Ni60 | Cr30Ni70 | Cr20Ni35 | Cr20Ni30 |
|
| Main chemical composition | Ni | Rest | 55.0~61.0 | Rest | 34.0~37.0 | 30.0~34.0 |
| Cr | 20.0~23.0 | 15.0~18.0 | 28.0~31.0 | 18.0~21.0 | 18.0~21.0 |
| Fe | ≤1 | Rest | ≤1 | Rest | Rest |
| Maximal Temperature(℃) | 1200 | 1150 | 1250 | 1100 | 1100 |
| Resistance Temperature correction coefficient.(CT) | 1.09±0.05 | 1.11±0.05 | 1.18±0.05 | 1.04±0.05 | 1.06±0.05 |
| Melting point (℃) | 1400 | 1390 | 1380 | 1390 | 1390 |
| Resistivityρ20℃(10-6Ω.m) | 800℃ | 1.008 | 1.078 | 1.028 | 1.188 | 1.173 |
| 1000℃ | 1.014 | 1.095 | 1.033 | 1.219 | 1.201 |
| 1200℃ | 1.025 | | 1.043 | | |
| Fast life value | Tem.(℃) | 1175 | 1100 | 1200 | 1050 | 1050 |
| hour(h) | ≥110 | ≥100 | ≥110 | ≥100 | ≥100 |
| Specific gravity(g/cm3) | 8.40 | 8.2 | 8.1 | 7.90 | 7.90 |
| Elongation(%) | ≥25 | ≥25 | ≥20 | ≥20 | ≥20 |
| Thermal(kj/m.h.℃) | 60.3 | 45.2 | 45.2 | 43.8 | 43.8 |
| Specific heat(20℃)j/g.℃ | 0.440 | 0.494 | 0.461 | 0.500 | 0.500 |
| Extend strength(20~1000℃)α*10-6℃ | 18.0 | 17.0 | 17.1 | 19.0 | 19.0 |
| Tensile strength(kg/mm2) | >85 | >85 | >85 | >85 | >85 |
| Repeatedly bending(F/R) | >12 | >12 | >12 | >12 | >12 |
| Microstructure | Austenitic | Austenitic | Austenitic | Austenitic | Austenitic |
nichrome wire resistance Notice
Resistance electric heating wire has strong antioxidant properties,
but a variety of gases in furnaces such as air, carbon, sulfur,
hydrogen and nitrogen atmosphere, still have a certain impact on
it.
Although these heating wires all have had antioxidant treatment,
the transportation, winding, installation and other process will
cause damage to a certain extent and reduce its service life.
In order to extend the service life, customers need to do pre
oxidation treatment before using. The method is to heat alloy
elements which have installed completely in the dry air to the
temperature (lower 100-200C than its maximum using temperature),
heat preservation for 5 to 10 hours, then cooling slowly with
furnace.
