Carbon fiber knitted fabric reinforced copper composite for sliding contact material

A novel carbon fiber knitted fabric reinforced copper (C/C–Cu) composite was fabricated by a pressureless infiltration technique. The microstructure of the composite was characterized by scanning electron microscopy, X-ray diffraction and energy dispersive spectroscopy. The mechanical, electrical and tribological properties of the C/C–Cu composite were compared with those of a carbon/copper contact strip. The experimental results showed that the C/C–Cu composite formed an interpenetrating network structure. It exhibited a high bending strength of 186 MPa, excellent impact strength of 4.7 J/cm2 and a particularly low electrical resistivity of 0.58 μΩ m, giving it advantages over the C/Cu strip in terms of both mechanical and electrical properties. Friction and wear experiments were conducted for the C/C–Cu composite and the C/Cu strip on a hemisphere pin-on-block apparatus, using cooper pins against polished specimens in dry sliding conditions. It was found that the C/C–Cu composite exhibited greater wear resistance than the C/Cu strip and did less damage to the copper pin.