Ensuring the surface quality of anisotropic crystals by applying oscillating movements

Anisotropic crystal is a difficult material to process due to its fragility and heterogeneous properties. A striking example is the KDP single crystal, which is used as a nonlinear optical element in heavy-duty lasers. This article provides an analysis of the main high-precision machining methods, namely: grinding, micro-sharpening, magnetorheological finishing (polishing). Cutting using oscillating movements is considered as an addition that allows to improve productivity, improve the quality of processing and ensure that the desired surface is obtained. The article provides examples of work that indicate the impracticability of using grinding due to the resulting defects. Limitations of micro-sharpening to ensure low roughness, as well as the emerging difficulties of magnetorheological finishing. As a result of the analysis based on empirical data, a reasonable solution was proposed in the form of the use of oscillating movements of the cutting tool, since this method allows to expand the possibilities of traditional processing, increasing the permissible cutting depth at times without losing the quality of the resulting surface.
EDN: KKVCPP, https://elibrary/kkvcpp

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