TYPE K (CHROMEL vs ALUMEL ) is used in oxidizing, inert or dry reducing atmospheres. Exposure to vacuum limited to short time periods. Must be protected from sulfurous and marginally oxidizing atmospheres. Reliable and accurate at high temperatures.
1. Chemical Composition
Material | Chemical composition (%) | ||||
Ni | Cr | Si | Mn | Al | |
KP(Chromel) | 90 | 10 | |||
KN(Alumel) | 95 | 1-2 | 0.5-1.5 | 1-1.5 |
2. Physical properties and Mechnical properties
Material | Density(g/cm3) | Melting pointºC) | Tensile Strength(Mpa) | Volume resistivity(μΩ.cm) | Elongation rate (%) |
KP(Chromel) | 8.5 | 1427 | >490 | 70.6(20ºC) | >10 |
KN(Alumel) | 8.6 | 1399 | >390 | 29.4(20ºC) | >15 |
3. EMF Value range at different temperature
Material | EMF value Vs Pt(μV) | |||||
100ºC | 200ºC | 300ºC | 400ºC | 500ºC | 600ºC | |
KP(Chromel) | 2816~2896 | 5938~6018 | 9298~9378 | 12729~12821 | 16156~16266 | 19532~19676 |
KN(Alumel) | 1218~1262 | 2140~2180 | 2849~2893 | 3600~3644 | 4403~4463 | 5271~5331 |
EMF value Vs Pt(μV) | ||||
700ºC | 800ºC | 900ºC | 1000ºC | 1100ºC |
22845~22999 | 26064~26246 | 29223~29411 | 32313~32525 | 35336~35548 |
6167~6247 | 7080~7160 | 7959~8059 | 8807~8907 | 9617~9737 |
4. Type ,designation and kind of thermocouples
Type | Designation | Thermocouple | Thermocouple Grade ID |
SC and RC | Copper-copper nickel 0.6 compensated compensating lead | Platonic-rhodium 10-platinum Thermocouple | S and R |
Platonic-rhodium 13-platinum thermocouple | |||
KCA | Iron-copper nickel 22 Compensated Compensating Lead | Nickel-chromium nickel thermocouple | K |
KCB | Iron-copper nickel 40 compensated compensating lead | ||
KX | Nickel-chromium 10-nickel 3 prolonged compensating Lead / compensating cable | ||
NC | Iron-copper nickel 18 compensated compensating lead | Nickel-chromium silicon-nickel thermocouple | N |
NX | Nickel-chromium 14 silicon-nickel 4 prolonged compensating lead / compensating cable | ||
EX | Nickel-chromium 10-nickel 45 prolonged compensating lead / compensating cable | Nickel-chromium-cupronickel thermocouple | E |
JX | Iron-copper nickel 45 prolonged compensating lead / compensating cable | Iron-constantan thermocouple | J |
TX | Iron-nickel-chromium 45 prolonged compensating lead / compensating cable | Copper-constantan thermocouple | T |
5. Production Process


