Tribological properties of materials used in biomedical implants critically affect the performance of the implant. Wear particles can cause aseptic loosening and adverse reactions in tissue/cells that may ultimately result in the need for replacement. Cobalt chromium (CoCr) is a popular material choice for implants due to its excellent wear resistance. Micromechanical and micro/nanotribological properties of CoCr alloy materials are investigated using microtribometry and atomic force microscopy (AFM). A ball-on-flat microtribometer using a tungsten carbide ball is used to examine tribological properties at contact areas of ~25-300µm² and contact pressures of ~100-400MPa. The onset of failure under reciprocating wear is investigated in both air and bovine serum, which more closely simulates the in vivo environment. To obtain a better understanding of the failure mechanisms of the material under load, the onset of failure under reciprocating wear in both air and bovine serum is investigated using AFM and SEM.