Surface properties of micro surface patterned Cp-Ti alloy via electrical discharge machining

Abstract

He process of machining micro surface patterns on a workpiece to improve various per- formance aspects of engineering materials, including wear resistance, corrosion resistance, and biocompatibility, has been a hot topic of research in recent years. Due to the restricted machinability of titanium and its alloys, it is very challenging to process micro surface pat- terns with exact surface geometries using traditional machining methods. Consequently, non-traditional processing techniques, such as laser, electro-erosion, and chemical etching, may overcome these obstacles. In the present study, electrical discharge machining (EDM) is used to form micro surface patterns on Cp-Ti alloy samples. First, graphite electrodes with several channels were manufactured, and then square-shaped surface patterns were processed onto Cp-Ti samples using EDM. To evaluate the machining performance of the process and surface features of the obtained micro surface patterns, the surface morphol- ogy and topography of the processed samples were investigated by scanning electron mi- croscopy (SEM) and three-dimensional (3D) optical profilometry, respectively. The average widths of the square-shaped surface patterns along the X and Y axes were 663.7±8 ?m and 609.5±4 ?m, respectively. For micro surface designs with square geometry, dimensional consistency was obtained with exceedingly small amounts of variation. However, a limited number of microcracks were observed due to rapid cooling during the processing of the surface patterns. The 3D surface topographies revealed that square-shaped micro surface patterns were successfully processed on the samples, indicating that micro surface patterns can be processed on Cp-Ti samples by using the proposed methodology, which has the potential for obtaining tailor-designed surface features, particularly for biomedical and tri- bological applications.