Requirements imposed to the properties of metals used as electrodes for thermocouples are as follows:
• reproducibility of material, ie possibility of obtaining of metal wires with the same properties;
• resistance of metal electrodes should be small and have a weak relationship vs temperature;
• stability of a static characteristic EAB = f(ϑ), ie recovery of properties after measurements;
• high sensitivity;
• correlation EAB = f(ϑ) should be close to linear relationship as much as possible.