Comparison of ordinary and cryogenic roller burnishing on surface and mechanical properties of 99.95% pure copper

Abstract In recent years, the surface finishing of parts and enhancing the surface properties of the material has been of considerable importance that researchers have always been looking for a way to enhance the polishing and its surface properties. Various processes are employed for this specific purpose. One of the best of these methods is burnishing, which in addition to creating excellent surface quality, also improves mechanical properties. In the present investigation, an examination was conducted to analyze and contrast the surface quality and mechanical characteristics of 99.95% pure copper sufobsequent to the burnishing operation, under both ordinary and cryogenic conditions. Experiments were conducted for single-pass and four-pass operations, while maintaining a constant rotational speed and utilizing two different feed rates of 0.09 and 0.2 mm rev −1 . It was observed that at a lower feed rate, greater number of passes and in cryogenic conditions, the burnishing process exhibited enhanced performance. Consequently, the resulting surface and mechanical characteristics, such as surface roughness, hardness, wear resistance, and grain refinement, showed more pronounced improvements. Cryogenic burnishing presented several benefits over ordinary burnishing. After four passes of cryogenic burnishing operation and under the feed rate of 0.09 mm rev −1 , the improvement rate of surface roughness was 42% higher compared to ordinary conditions. This further improvement was observed for other mechanical properties of material as well. In particular, an additional enhancement of 9.6% in hardness, 19% in grain refinement, and 9.3% in wear resistance underscore the efficacy of this method compared to ordinary burnishing process.