Patent UA-97453-C2 (UA)
Title: Method for determination of main parameters of three-dimensional structure of metal materials
Inventor: DANILENKO TETIANA PETRIVNA
IPC: G01N21/00
Filed: 2011-01-31
Abstract: The invention relates to the area of metallographic investigations and analysis of granular structure of metal materials, methods for determination of its main parameters. The method for determination of main parameters of volumetric structure of metal materials is based on reconstruction of distribution of dimensions of three-dimensional volumetric grains on basis of information obtained on flat cross section on metallographic section through solving systems of linear equations that characterize the ratio of distributions of dimensions of three-dimensional volumetric grains P(D) and flat P(d) and linear P(l) cross-sections of those on a section, with determination of numerical characteristics of main parameters of spatial structure in volume. Initial information for reconstruction of distribution of dimensions of three-dimensional volumetric grains is information from flat cross section of the structure on metallographic section as distribution in given dimensional scale of lengths of chords P(l), obtained as result of cross section of secant lines applied to the image of granular structure on the section with boundaries of the set of grains chosen for analysis. First for account of form of flat cross sections of the grains at minimal statistically necessary number of those one determines coefficients of form β, those are found for each dimensional interval of scale from the ratio of average respective parts of chords P(l)of those typical flat cross sections of grains to respective calculated relative parts of chords from circle, then one carries out reconstruction of distribution of dimensions of flat cross sections of grains P(d) through solving systems of linear equations to which form coefficients βfound are introduced, and in which determined proportional dependence of probability of flat cross section of grain to secant line on its dimension determined is taken into account. Then for account of form of three-dimensional volumetric grains on minimal statistically necessary number of typical in form maximal flat cross sections of grains present at the image of the structure one determines form coefficients αfrom the ratio of average relative parts of chords P(l)from those maximal flat cross sections of grains to respective calculated relative parts of diameters of flat cross sections of a sphere, and then one carries out reconstruction of distribution of determination of dimensions of three-dimensional grains P(D) through solving a system of linear equations to which one introduces form coefficients αfound, and in which proportional dependence of probability of a three-dimensional grain falling to secant plane on its dimension is taken into account. Then on basis of distribution of dimensions of three-dimensional volumetric grains P(D) determined one founds main parameters of volumetric structure. The method makes it possible to increase accuracy of values of main parameters of structure found, at provision along with that of increase of technological capabilities.