BARRIER LAYERS BASED ON REFRACTORY METALS IN CONTACTS OF HIGH TEMPERATURE THERMOELEMENTS

An electrochemical method is proposed for forming contacts to high-temperature thermoelements with barrier layers based on refractory metal alloys. The contacts are intended for thermoelements with operating temperatures of up to 900 K. The barrier layers had a specific resistance of no more than 15.3*10-8 Ohm m, and a specific contact resistance of no more than 1.5*10-9 Ohm m2. The best results were obtained for barrier layers based on Mo-Ni alloy with a Mo content of 36.5 wt.%. Ag films obtained by electrochemical deposition were used as a commutation layer in the contacts. It has been established that the contacts are thermally stable at the limiting operating temperatures of thermoelements and have an adhesive strength of at least 10.3 MPa.