An approach for quantification of friction and enhancing the process efficiency during polishing of optical glass

다국어 초록 (Multilingual Abstract)

Quantification of friction may provide insights into the material removal behavior of polishing process. In this study, frictional force at the workpiece-polisher interface is measured using customised instrumentation setup (miniature load cell: 0-25 lbf) at different combinations of process parameters during polishing of BK7 optical glass. It is observed that frictional force varies with polishing time and is also a function of process parameters. It is observed that friction coefficient (~0.1) indicates the ductile material removal from the workpiece surface while friction coefficient (~0.3) indicates ductile cum brittle fracture behavior, which is also verified through surface texture observed through optical interferometer. Friction coefficient indicates that workpiece and polisher surfaces are in solid-solid contact mode.
Hence, mechanical actions are dominant over chemical actions in removing the material from workpiece surface. Further variation of surface parameters w.r.t. wear index is estimated and way to enhance the polishing process efficiency is suggested.

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