Effect of tribolayer formation on corrosion of CoCrMo alloys investigated using scanning electrochemical microscopy.

Scanning electrochemical microscopy was used to probe the topography and electrochemical activity of CoCrMo alloys mechanically polished in the presence of bovine calf serum (BCS) in a hip simulator. These substrates are made of the same alloy used in metal-on-metal bearings for artificial hip joints. The BCS serves as an in vitro substitute for the synovial fluid which forms a lubricant in the actual orthopedic device.