Effect of the Binder during Ultra-Precision Polishing of Tungsten Carbide Using a Semirigid Bonnet Tool

Abstract

Tungsten carbide (WC) has the characteristics of high hardness, high strength, corrosion resistance, wear resistance and excellent fracture toughness. Accordingly, it has been commonly used as the material for cutting tools and molds in glass-forming techniques. To obtain ultra-smooth surfaces, fine polishing of WC is indispensable. However, the efficiency of WC polishing is low using the existing polishing methods, and the mechanism behind the polishing process requires further investigation. Specifically, the effect of the binder in WC polishing is not clear since there are different kinds of WC with various weight percentages of the binder. In this paper, we present the findings of a study on the polishing performance of two kinds of WC material, with and without the binder, using a semi-rigid (SR) bonnet polishing tool. A series of experiments were performed on a 6-DOF robotic polishing instrument to investigate the material-removal characteristics, surface integrity and sub-surface damage after polishing. The results demonstrate that the SR bonnet polishing tool successfully reduced the surface roughness of WC with and without the binder to the nanometric level, though the lowest surface roughness was obtained on binder-less WC. No obvious sub-surface damage was observed under SEM inspection, while the processing efficiency was greatly improved owing to the high material removal rate of the tool. Based on our analysis of key polishing parameters and corresponding surface integrities, the effect of the binder on the polishing performance is explained, which offers excellent guidance for WC polishing.

The state‐of‐art review of ultra‐precision machining using text mining: Identification of main themes and recommendations for the future direction

“…Interacted theme members Content example 1 and 4 Spindle/motion/vibration and measurement/error Effects of the motion from spindle vibration on machined quality of UPM (Sun et al, 2018;Zhang et al, 2018) 2 and 3 Optical/component and polishing/ large Ultra-precision polishing on large scale workpiece (Fan et al, 2021) 2 and small themes Micro and structure/nano • Freeform surface on optical material surfaces (Lyu et al, 2022) • Fabrication of microstructural surface with hierarchical micro/nano structures by UPM (Lemos et al, 2022) 3 and small themes Polishing and efficiency/ performance/analysis Efficiency and performance using ultra-precision polishing technology (Ke et al, 2022;Tan et al, 2022) drive device, have improved UPM machining accuracy and flexibility in fabricating micro-structures (Zhang et al, 2019).…”