Manufacturing methods for machining micro pits of hip implant for metal-on-metal lubrication

Hip implant is an orthopedic procedure which the hip joint is replaced by prosthetic or artificial implant in order to replace arthritic or dysfunctional joint surface. The process is also known as hip arthroplasty. However, the metal-on-metal hips articulation suffers from friction due to the moving metal surface thus, shortening the surviving of the joint. A micro pits formation is therefore used for lubrication purpose, which eventually prolong the lifespan of the hips. This paper will focus on the methods for machining the micro pits in terms of work piece placement, coordination and orientation related to the electrode of electrical discharge machining system for lubrication purpose. A new structure of work piece positioning system would be designed accordingly in order to optimize the machining performance and improve lubrication activities in the hip implant device.