Evaluation and Comparison of the Arc Erosion Characteristic of Ag/SnO_2/In_2O_3 Contact Materials Used for an Automotive Relay

摘要

The arc erosion characteristic of contact materials is one of the key factors for the electric life of a relay. A new simulation testing device used for evaluating the arc erosion characteristic was built in order to meet the need of engineering application, and its action characteristic was almost the same as relays. The reliability and availability of the simulation testing device were confirmed by lots of designed parameter testing and analysis. The arc erosion characteristic of Ag/SnO_2/In_2O_3 contact materials with different content of oxides and prepared methods was evaluated and compared by this apparatus. The research results indicated that the arc erosion of Ag/SnO_2/In_2O_3 prepared by the same method became less with the increasing content of oxides, whatever the load type is lamp or resistance. Compared with the alloy internal oxidation (I.O.) method and power pre-oxidation (P.M.) method, the arc erosion of Ag/SnO_2/In_2O_3 prepared by the former was less. Because of the existence of TeO_2, the abilities of anti arc erosion and material transference of contact materials were improved. Moreover, this oxide may be beneficial for the characteristic of anti welding, and it was further identified by the electric life experiment of relays.