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.<>