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When studying the regularities inherent in the effect of intermolecular interaction between polishing powder particles and a treated material on the material removal rate in the process of polishing and the roughness of the polished surfaces of optical parts and elements, which are manufactured of glass, sitalls, and optical and semiconductor crystals, it has been established that the material removal rate linearly decreases with an increase in the Lifshitz constant and the potential of molecular interaction between a disperse phase particle and a treated surface. It has been shown that the material removal rate in the course of polishing and the roughness parameters of treated surfaces decrease with an increase in the transfer energy. It has been established that the ratio η/Ra linearly grows with a decrease in the Lifshitz constant. It has been demonstrated that the required level of material removal rate and roughness can be attained for treated surfaces by using a disperse polishing system of micro- and nanopowders.

The study of the regularities of the polishing of optical glass and glass ceramics showed that the coefficient of surface tension, the coefficient of dynamic viscosity of the polishing dispersed system, and the contact angles of the surfaces of the treated surface and lapping tool affect the thickness of the gap between them and, accordingly, the productivity of removing the processed material and the roughness parameters of the treated surfaces. The energy transfer is directly related to the coefficient of volumetric wear, which determines the productivity of polishing. The validity of the ratio between the coefficients of volumetric wear and thermal diffusivity, depending on the specific heat capacity, transfer energy, and temperature, is confirmed. An increase in the thickness of the gap between the treated surface and the lapping tool leads to a decrease in the most probable size of sludge particles and an improvement in the roughness of polished surfaces.

The in-process monitoring of surface shape of optical surfaces directly in the course of polishing is demonstrated to be accomplished through the confocal chromatic imaging technology. A linear relationship has been found between the deviation from square waveform and the variation of the workpiece surface shape.

Based on the physical-statistical model of formation of workpiece material debris particles in diamond polishing, an analysis of removal rate and form accuracy has been performed for flat surfaces of optoelectronic components made of quartz, aluminum nitride, and gallium nitride. The most efficient values of kinematic parameters of machine tool setting have been defined to achieve the required shape-generation accuracy. The paper provides some findings of the experimental verification of calculated data on the removal rate in polishing and the form deviation of the machined surfaces.

A study of the mechanism of formation of monocrystal planes of different crystallographic orientations has revealed that in polishing of sapphire the surface roughness parameters Ra, Rq, Rmax decrease in the series c > r > m > a with decreasing dielectric permittivity and thermal conductivity coefficient of the workpiece material, debris particle height, and Lifshitz constant that represents the energy of interaction between the polishing powder grains and the workpiece surface. The minimum allowable values of surface roughness parameters for atomically smooth surfaces have been defined, which linearly depend on interplanar spacings and decrease in the series r > a > c > m.

Based on investigations of the mechanism of precision surface formation in workpieces of anisotropic monocrystalline materials for optoelectronics, a generalized model of material removal in polishing with suspensions of polishing powders has been constructed. The removal rate in polishing sapphire planes of different crystallographic orientations has been found to grow in the series m < c < a < r with increasing volume, surface area, and most probable size of debris particles as well as with energy of dispersion of material from the face being polished.

The authors of this paper have substantiated the appropriateness of application of polishing suspensions of diamond micron powders, boron nitride and Ti3AlC2 MAX-phase powders in the study of the mechanism of polishing monocrystalline silicon carbide. They have proved suitability of using the following parameters as criteria for efficiency of the machining process: the specific value of the energy of transfer, the density of the energy of transfer, and the density of vibrational energy spent for the formation of debris particles. Computer modeling of the polished surface micro- and nanoprofile produced the profile charts from which the surface roughness parameters have been determined and the characteristic relations between the parameters and the most probable debris particle size have been defined.

The investigation of the mechanism of diamond-abrasive finishing of monocrystalline silicon carbide on the basis of a generalized model of formation and removal of debris particles and material removal has demonstrated that the use of specific value of the energy of transfer as a criterion for the assessment of machining efficiency permits substantiating suitability of boron carbide and titanium dioxide powders for fine grinding and of chromium oxide, alumina, ceric oxide, and ASM 2/1 diamond micron powders for ultrafine grinding.

Polished surface roughness is shown to depend on a ratio of natural vibration frequencies of molecular fragments on the tool and workpiece surface. The factors that have the greatest effect on the machined surface roughness are the following: (a) the number of molecular fragments the debris particles consist of, (b) the most probable size of the particles, (c) natural vibration frequencies of the fragments of the tool and workpiece materials, (d) workpiece material thermal conductivity, and (e) machining conditions.

The paper presents a procedure for measuring laser radiation reflection and scattering coefficients of polished nonmetallic workpieces. A relation between the scattered light intensity and the polished surface roughness is studied. It is demonstrated that colorimetric characteristics of nonmetallic materials can be determined from the light scattering and reflection coefficients.