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We report on what we believe to be a novel classification method for polishing processes that we apply in our laboratory on a regular basis. Two parameters are deduced from the in situ iTIRM (intensity-detecting total-internal-reflection microscopy) measurement method. Contrary to Preston's law, which gives the removal rate, the parameters of the iTIRM process are a measure of the change in surface quality (roughness, subsurface damage, and scratch and dig) and the duration of the polishing process.

A variation on the fluid jet polishing (FJP) technique, arbitrarily named Jules Verne (JV), will be described in this article. Jules Verne is a glass processing technique that removes material due to the fact that the tool and the surface are in close contact, and a slurry moves in between the tool and the surface. This approach has both advantages and disadvantages with respect to the original FJP modus: it enables a feed-controlled machining process, but deeper lying areas are harder to reach. A simulation model will be presented that predicts the flow of the slurry in the Jules Verne setup, which is followed by the computation of the trajectories of the particles in the flow. Furthermore, experimental data will be reported demonstrating the feasibility of the JV idea. A model will also be presented simulating the interaction between the surface and the impinging abrasives at a microscopic level, enabling the prediction of the final surface roughness.Keywords: polishing, shaping, abrasive fluid jet, roughness INTRODUCTIONThis article will cover the novel idea of polishing with the so called Jules Verne technique, a new polishing technique that is related to Fluid Jet Polishing (FJP) [1]. Similar to PACE (plasma assisted chemical etching), a small cup-wheel like tool is positioned within a Computer Numerically Controlled (CNC) machine close to the surface to be machined. An abrasive slurry is fed into the cup wheel along its axis of symmetry. If the gap between tool and workpiece is small enough, pressure is built up within the cup wheel and material removal is achieved along the circular edge of the rotating cup wheel. The advantage of this approach is that it enables a feed-controlled machining process. This article will cover the experimental setup that has been built on a computer numerically controlled machine (Section 2), a simulation of the flow of the slurry will be treated in Section 3, the results of some initial experiments will be described in Section 4, and some issues concerning the final roughness of the treated surface will be covered in Section 5. JULES VERNE The setupThe new method for shaping, shape corrections and polishing that has been invented and that is the subject of this article is arbitrarily named Jules Verne (JV). The new method works with abrasives in water, just like in the case of FJP, but it removes material by moving abrasive particles over the surface in a fashion comparable to that in the case of PACE (plasma assisted chemical etching). A small cup-wheel like tool is positioned within a CNC machine close to the surface to be machined. An abrasive slurry is fed into the cup wheel along its axis of symmetry. If the gap between tool and workpiece is small enough (typical stand-off distance of 50 µm), pressure is built up within the cup wheel and material removal is achieved along the circular edge of the rotating cup wheel. The velocity in the main chamber of the nozzle is not high enough to remove material, but when the slurry leaves the nozzle it accelerates to pass t...

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