Type K is one of the most common general industry thermocouple not only in Western Australia but also WorldWide. Type `K` thermocouple has sensitivity approx. 41μV / °C.
Studies of metals shows that type `K` has 2 wires inside `positive wire +` stands for Chromel and `negative wire -`stands for Alumel
Chromel consist 90% nickel and 10% chromium
Alumel consist 95% nickel and 2% aluminum and 1% silicon
Type K thermocouple temperature range is -270 to 1372°C.
Melting point 1400°C.
Are you doing assembly and not sure which wire is negative? Simple use magnet and negative wire is that which interact with it.