Investigation of electric and wear phenomena of liquid metal wetted copper fiber brushes under conditions of high slip ring eccentricity

Metallic fiber brushes wetted with a liquid metal could potentially provide a current collector for large scale homopolar machinery. This study investigates brushes composed of copper fibers swaged together at one end and wetted with the liquid metal, Nak78. The brushes are forced to carry current while an eccentric slip ring compresses and releases the fibers, modeling the effect of rotor runout in a full scale collector. Preliminary studies indicate that these brushes are not transferring noise free steady current nor maintaining low levels of wear.