Superfinishing of Femoral Head Prosthesis Implants



Minimize the scratches on the finished Femoral Head to maximize productivity by reducing the amount of hand polishing.
Process: Finish the OD of a Femoral Heads using multiple wheels of decreasing grit size to achieve the desired finish and geometry.
Component: Femoral Head
Material: Cobalt Chrome
Hardness: 50 Rc
Stock Removal: 150 Microns (0.006")
Coolant: Light Mineral Seal Base Oil
Requirements: Roundness 5 Microns (0.0002")
Diametric Size 15 microns(0.0006")
Finish 0.015 um Ra (0.6 u" Ra)
Machine Setup: 3 Silicon Carbide Wheels - Turret Mounted
Wheel Specification: GC320-50DV2S
Wheel Size: 34 x 45 x 24mm (1.340" x 1.75" x .945")


Darmann implemented the use of wheels having coolant release holes that helped to keep the wheel/part interface free of debris. This new wheel design improved part quality and reduced process costs resulting in:
A 30% reduction in hand polishing
A 25% improvement in overall productivity
Improved quality and part appearance by reducing scratching on the surface of the part