sino Published in 2011-08-02
Nicrosil-Nisil thermocouple is the latest base metal thermocouple, developed to improve the drawbacks that type K thermocouple has. The main chemical composition of positive leg Nicrosil(NP) is Ni: Cr: Si≈84.4: 14.2: 1.4; negative leg Nisil (NN) is Ni: Si: Mg≈95.5: 4.4: 0.1. Type N thermocouple also be used in the similar atmospheres that type K works, and the operating temperature range is -200~1300℃。
Type N thermocouple improves the EMF drift and short term EMF change, compared to type K thermocouple, and has a longer life than type K thermocouple. Therefore, in the industries where temperature control and measurement are especially critical, type N thermocouple has more advantages than other thermocouple as it has long life and stable thermal EMF.
| TYPE | Chemical Composition% | ||||
| Ni | Cr | Mn | Si | Mg | |
| NP | rest | 13.7~14.7 | / | 1.2~1.6 | 0.01 |
| NN | rest | 0.02 | / | 4.2~4.6 | 0.5~1.5 |
Standard: IEC60584-1
| TYPE | EMF Versus Pt.67(mv) | ||||||
| 100℃ | 200℃ | 400℃ | 600℃ | 800℃ | 1000℃ | ||
| NP | 1.755~1.813 | 3.910~3.976 | 8.880~8.959 | 14.307~14.433 | 20.012~20.180 | 32.313~32.525 | |
| NN | 0.975~1.005 | 1.954~1.988 | 4.035~4.075 | 6.212~6.274 | 8.318~8.402 | 8.807~8.907 | |
| NP-NN | 2.730~2.818 | 5.864~5.962 | 12.915~13.033 | 20.519~20.707 | 28.330~28.582 | 8.807~8.907 | |
PhysicalProperties:
| Type | Density at 20℃ （g/cm³） | Melting point （℃） | Tensile Strength(Soft annealed condition in 20℃)（Mpa） | Elongation(Soft annealed condition in 20℃)（%） | Resistivity at 20℃ (μΩ.m) |
| NP | 8.5 | 1410 | ≥620 | ≥25 | 0.97 |
| NN | 8.6 | 1340 | ≥550 | ≥30 | 0.33 |
