Nickel chromium nickel silicon thermocouple wire (Type K)
Nickel chromium nickel silicon thermocouple (K-type thermocouple) is the low metal thermocouple with the largest usage in the temperature measurement area above 500 ℃, and its usage is the sum of other metal thermocouples. The nominal chemical composition of the positive pole (KP) is Ni: Cr ≈ 90:10, and the chemical composition of the negative pole (KN) is Ni: Si ≈ 97:3, and its operating temperature range is - 200~1300 ℃.
K-type thermocouple has the advantages of good linearity, large thermoelectric electromotive force, high sensitivity, good stability and uniformity, strong oxidation resistance, low price, etc. It can be used in oxidizing and inert atmosphere.
Type K thermocouples cannot be directly used in sulfur, reducing or alternate reducing and oxidizing atmospheres and vacuum at high temperatures, nor are they recommended for weak oxidizing atmospheres.