Nisil is an austenitic nickel-silicon alloy (NiSi alloy) used for the negative leg of thermocouple type N. It offers better oxidation resistance than type E, J and K thermocouples.
Nisil alloy cannot be exposed to sulphur-containing gases. This thermocouple alloy is the most recent one among the different types covered by the international standards.
Mechanical properties
| Yield strength | Tensile strength | Elongation |
|---|---|---|
| Rp0.2 | Rm | A |
| MPa | MPa | % |
| 300 | 680 | 33 |
Properties are measured on wire Ø 2 mm
Physical properties
| Density g/cm3 | 8.59 |
|---|---|
| Electrical resistivity at 20°C Ω mm2/m | 0.36 |
| Temperature °C | Thermal Expansion x 10-6/ K |
|---|---|
| 20 - 100 | 17 |
| Temperature °C | 20 |
|---|---|
| W m-1 K-1 | 17 |
| Temperature °C | mV |
|---|---|
| 100 | 2.774 |
| 200 | 5.913 |
Size range
Standard sizes for thermocouple strip range from thickness 0.10 to 3.0 mm (0.0039 to 0.181 inch) and width from 4 to 195 mm (0.157 to 7.68 inch).
| Melting point °C | 1420 |
|---|---|
| Magnetic properties | The material is non- magnetic. |