Surface finishing of cobalt chromium alloy femoral knee components

This paper describes the modification of surface roughness and lay of cobalt chromium alloy femoral knee components by magnetic abrasive finishing (MAF), including clarification of the MAF surface-processing mechanisms. The MAF process creates characteristic surfaces by micro-cutting of abrasive pressed by magnetic particles that nearly conform to the surface, removing large asperities and creating microasperities compared to hand-buffed surfaces. The process enables smoothing the surface on the nanometer scale with critical control of surface lay (e.g., crosshatch angle), altering the contact angle of water by a combination of kinematic behavior of magnetic particles over the freeform condyle surface.