Metal matrix contact surfaces for high current applications

Summary form only given. Results are reported concerning recent advances in metal matrix-material fabrication showing that wear-resistant materials can be combined with conductive binders to produce current collectors with low-wear and high current-carrying capabilities for use as rotor disks in high-current multimegawatt homopolar machines. The author gives a description of the dynamic wear testing machine used to test various material combinations. The results of the testing showed that an aluminium bronze matrix was superior to a copper matrix due to its intrinsic hardness. Additionally, it is generally concluded that: (1) conductive ceramics can reinforce conductive metals and provide an increase in wear resistance, while sacrificing some conductivity; (2) lubrication reduces wear in materials, specifically adhesive wear, and controls interface temperatures; and (3) systems approach to defining wear pair compatibility is needed to better define the responses of material to high currents and sliding velocities. For the author´s purposes the wear tester designed and built best fits this description, but materials compatibility work is still needed to optimize the disk and brush materials.<>