Theoretical and experimental investigation of 3D-structured surface generation by computer controlled ultra-precision polishing

i Abstract of thesis entitled ‘Theoretical and Experimental Investigation of 3D-Structured Surface Generation by Computer Controlled Ultra-Precision Polishing’ submitted by Ho Lai Ting for the degree of Doctor of Philosophy at The Hong Kong Polytechnic University Three-dimensional (3D) structured surfaces have been widely used in different applications such as self-adhesive sensors, compound lenses for holography in phonics products, bionic applications, bio-medical areas, etc. Although there have been some research studies on the manufacture and machining of 3D-structured surfaces, the research work is still far from complete. The current fabricating process, for instance, laser and etching, for 3D-structured surface generation are expensive and time-consuming. Computer Controlled Ultra-precision Polishing (CCUP) is capable of fabricating ultra-precision freeform surfaces with sub-micrometre form accuracy and surface roughness in the nanometre range. CCUP consists of Mechanical Polishing (MP) and Fluid Jet Polishing (FJP) processes. Although polishing is a historic machining process, research on the polishing mechanics and surface generation during the polishing process is still far from complete. Polishing is a multi-step process that involves a sequence of steps with different process and material parameters. “What parameters should be used for the next step” is always a question asked by operators. They make their decisions by measuring the surface after each polishing step. Moreover, the achievement of desirable polished surfaces still depends largely on the expensive and time-consuming trial-and-error approach when new materials, new designs of 3D-structured surfaces or new machine tools are used. An appropriate