Chromel
Chromel is an alloy made of approximately 90 percent nickel and 10 percent chromium that is used to make the positive conductors of ANSI Type E (chromel-constantan) and K (chromel-alumel) thermocouples. It can be used up to 1100 °C in oxidizing atmospheres. Chromel is a registered trademark of Concept Alloys, Inc.
| CHARACTERISTICS: | |
|---|---|
| Temperature coefficient | 0.00032 K−1 |
| Electrical resistivity | 0.706 µΩ m |
| Mechanical properties | |
| Elongation at break | <44% |
| Izod impact strength | 108 J m−1 |
| Modulus of elasticity | 186 GPa |
| Tensile strength | 620–780 MPa |
| Physical properties | |
| Density | 8.5 g cm−3 |
| Melting point | 1420 °C |
| Thermal properties | |
| Coefficient of thermal expansion | 12.8×10−6 K−1 at 20–1000 °C |
| Maximum use temperature in air | 1100 °C |
| Thermal conductivity | 19 W m−1 K−1 at 23 °C |
Chromel A
Chromel A is an alloy containing 80% of nickel and 20% chromium (by weight). It is used for its excellent resistance to high-temperature corrosion and oxidation. It is also commonly called Nichrome 80-20 and used for electric heating elements.
Chromel C
Chromel C is an alloy containing 60% nickel, 16% chromium, and 24% iron. It is also commonly called Nichrome 60 and is used for heating elements, resistance windings, and hot wire cutters.