Abstract The use of copper–beryllium (UNS C17200) was demonstrated as a low wear, highly compliant material for the construction of high current density metal fiber brushes. Testing was conducted in a humidified carbon dioxide environment. Brush linear wear rates of 4 × 10 −11 m/m were achieved at sliding speeds and current densities as high as m/s and 215 A/cm 2 (2 MA/m 2 ). Contact ...