Ni70Cr30 NiCr Alloy Lead Bar Rod High Resistance Round Bar For
Electrical High Temperature Heater
Nichrome (NiCr, nickel-chrome, chrome-nickel, etc.) is any of variousalloys of nickel, nichrome and often iron (and possibly other elements). The most common usage is as resistance wire, although they are also used in some dental restoration (fillings) and in a few other applications.
Application:
Almost any conductive wire can be used for heating, but most metals
conduct electricity with great efficiency, requiring them to be
formed into very thin and delicate wires in order to create enough
resistance to generate heat. When heated in air, most metals then
oxidize quickly, become brittle, and break. Nichrome wire, however,
when heated to red-hot temperatures, develops an outer layer of
chromium oxide, which is thermodynamically stable in air, is mostly
impervious to oxygen, and protects the heating element from further
oxidation.
Nichrome is used in the explosives and fireworks industry as a bridgewire in electric ignition systems, such as electric matches and model rocket igniters.
Industrial and hobby hot-wire foam cutters use nichrome wire.
Nichrome wire is commonly used in ceramic as an internal support
structure to help some elements of clay sculptures hold their shape while they are still soft. Nichrome
wire is used for its ability to withstand the high temperatures
that occur when clay work is fired in a klin.
Nichrome wire can be used as an alternative to platitum wire for
flame testing by colouring the non-luminous part of a flame to
detect cations such as sodium, potassium, copper, calcium, etc.
Other areas of usage include motorcycle mufflers, in certain areas
in the microbiological lab apparatus, as the heating element of
plastic extruders by theRepRap 3D printing community, in the solar
panel deployment mechanism of spacecraft Lightsail-A, and as the heating coils of electric cigarretes.
The alloy price is controlled by the more expensive nickel content.
Distributor pricing is typically indexed to market prices for nickel.
Nichrome alloys are known for their high mechanical strength and
their high creep strength. The properties of nichrome vary
depending on its alloy. Figures given are representative of typical
material and are accurate to expressed significant figures. Any
variations are due to different percentages of nickel or chromium.
| Properties Grade | NiCr 80/20 | NiCr 70/30 | NiCr 60/15 | NiCr 35/20 | NiCr 30/20 |
Main Chemical Composition% | Ni | Balance | Balance | 55.0-61.0 | 34.0-37.0 | 30.0-34.0 |
| Cr | 20.0-23.0 | 28.0-31.0 | 15.0-18.0 | 18.0-21.0 | 18.0-21.0 |
| Fe | ≤1.0 | ≤1.0 | Balance | Balance | Balance |
| Max Continuous Service Temperature(°C) | 1200 | 1250 | 1150 | 1100 | 1100 |
| Resisivity (uΩ.m,20°C) | 1.09 | 1.18 | 1.11 | 1.04 | 1.04 |
| Density (g/cm3) | 8.4 | 8.1 | 8.2 | 7.9 | 7.9 |
| Thermal Conductivity(KJ/m·h·°C) | 60.3 | 45.2 | 45.2 | 43.8 | 43.8 |
| Coefficient of Thermal Expansion(α×10-6/°C) | 18.0 | 17.0 | 17.0 | 19.0 | 19.0 |
| Melting Point( °C) | 1400 | 1380 | 1390 | 1390 | 1390 |
| Elongation(%) | ≥20 | ≥20 | ≥20 | ≥20 | ≥20 |
| Micrographic Structure | austenite | austenite | austenite | austenite | austenite |
| Magnetic Property | nonmagnetic | nonmagnetic | nonmagnetic | nonmagnetic | nonmagnetic |
| Properties Grade | NiCr 80/20 | NiCr 70/30 | NiCr 60/15 | NiCr 35/20 | NiCr 30/20 |
Main Chemical Composition% | Ni | Balance | Balance | 55.0-61.0 | 34.0-37.0 | 30.0-34.0 |
| Cr | 20.0-23.0 | 28.0-31.0 | 15.0-18.0 | 18.0-21.0 | 18.0-21.0 |
| Fe | ≤1.0 | ≤1.0 | Balance | Balance | Balance |
| Max Continuous Service Temperature(°C) | 1200 | 1250 | 1150 | 1100 | 1100 |
| Resisivity (uΩ.m,20°C) | 1.09 | 1.18 | 1.11 | 1.04 | 1.04 |
| Density (g/cm3) | 8.4 | 8.1 | 8.2 | 7.9 | 7.9 |
| Thermal Conductivity(KJ/m·h·°C) | 60.3 | 45.2 | 45.2 | 43.8 | 43.8 |
| Coefficient of Thermal Expansion(α×10-6/°C) | 18.0 | 17.0 | 17.0 | 19.0 | 19.0 |
| Melting Point( °C) | 1400 | 1380 | 1390 | 1390 | 1390 |
| Elongation(%) | ≥20 | ≥20 | ≥20 | ≥20 | ≥20 |
| Micrographic Structure | austenite | austenite | austenite | austenite | austenite |
| Magnetic Property | nonmagnetic | nonmagnetic | nonmagnetic | nonmagnetic | nonmagnetic |
