Improvement of Corrosion Resistance in Metallic Biomaterials using a New Electrical Grinding Technique

A new electrical grinding method for the fabrication of machined surfaces with desirable characteristics for biomaterials and other engineering applications is presented. Conventional biomaterials, such as stainless steel and titanium alloy, require enhanced chemical stability and wear resistance, which are dependent on the quality of the surface oxide layer. However, it is difficult to produce sufficiently homogenous oxide layers by alumina polish finishing alone. The electrical grinding method proposed in this study, in which electric current is applied to the grinding fluid in the machining process, improves oxide formation on the finished surfaces, thereby realizing finished surfaces with extremely thick and stable oxide layers. Compared with alumina polishing, electrical grinding yields machined surfaces having excellent corrosion resistance.