Determining favourable process parameters in computer numerically controlled polishing of metal surfaces

Abstract

Traditionally, metal surface polishing has been an important high precision process that has mostly been carried out manually, due to its high complexity and the difficulty in controlling many process parameters simultaneously. In this work a prototype polishing jig that offers elementary force control capability is utilised in order to perform flat metal surface polishing experiments based on trochoid toolpaths. The goal of this study is to optimise polishing speed, feed rate and force levels by designing Taguchi experiments and implementing subsequent ANOVA for three successive polishing stages (grinding, lapping and finishing) while following a certain polishing method (tool and diamond paste combination), which is standard knowledge contributed by domain experts. The Taguchi approach ultimately fine-tunes the polishing procedures, ensuring that the results are both consistent and optimal, the pertinent criterion being the roughness of the polished surface. [Submitted 5 December 2018; Accepted 21 October 2020]