Petasyuk G. Scientific Fundamentals of the Complex Estimation of the Quality of Synthetic Diamond and CBN Powders to be Used in Abrasive Tools Making

The important scientific-applied problem of necessity of increasing the perfection level and intensification of estimating the quality of synthetic diamond (SD) and cBN powders was solved. The problem was solved by means of an integrated approach to generalization of indices of technological properties of the powders as features of quality, introduction of the concept of integral homogeneity as a new feature of quality and application of developed differential-oriented 3D approximation to the real shape of each grain in large set of grains. That has great practical value for the process of production of the powders and follow-up manufacturing of the abrasive tools from the powders. A new method of estimating the diamond powders quality by integral homogeneity was developed. Advanced extrapolation-affine 3D model of grain of SD powders was proposed. The methodology of the new 3D grain model application for computation of external specific surface, the number of grains in one carat of the powder, heap density and indices of sieve grain distribution of SD powders was developed. New methods for determination of the characteristics of SD grinding powders, which are significant for the diamond-abrasive machining, were developed. A new system-analog method for identification of geometrical shape of diamond grain projection was developed. The interrelation of geometry of the grain projection and morphometric characteristics of the SD powders with the static strength and abrasive ability of the powders was ascertained. The close relationship of the adsorption potential of micron, submicron and nanopowders of SD to the total specific surface of the powders was found. Effect of elemental composition of growth system of synthesis, methods and technological factors of processes of production and modifying of SD grinding powders on the powder characteristics was studied. A new approach to the problem of substantiation of choice of SD grinding powders as tool material for diamond-abrasive machining was proposed. Experimental-industrial checking of the results of the dissertation was carried out.