National University of Science and Technology “MISiS”, Moscow, Russia:

A. V. Kudrya, Professor of a Chair of Metal Science and Physics of Strength, e-mail: AVKudrya@misis.ru
E. A. Sokolovskaya, Assistant Professor of a Chair of Metal Science and Physics of Strength
T. Sh. Akhmedova, Post-Graduate Student of a Chair of Metal Science and Physics of Strength
V. Yu. Perezhogin, Post-Graduate Student of a Chair of Metal Science and Physics of Strength

The complex of hard alloys’ facing properties is determined by their structure. However, the requirements to their structure are often of a qualitative character. Their evaluation is based on the comparison with a standard (picture) or a verbal description. To quantify the structure, it is necessary to measure the individual elements and their totality as a whole. In this regard, the use of computerized procedures is promising.However, they have not become widespread yet. The main reason is in the difficulty of their formalization, considering the nature of the analyzed object and metrological provision of measurements needed. This refers to the choice of algorithms for the primary image binarization and the choice of noise filtering criteria. In this work, in particular, depending on the type of structure, methods of local (on the scale of a single element) and a single (for the whole field of view) binarization of the image were successfully tested. A partition of the space into Voronoi polygons was used to estimate the inhomogeneity of particles arrangement in the field of a thin section. The Voronoi polygons statistics are useful for the objective isolation of clusters of hardening particles (where destruction is easier) and sparse regions (deformation is easier). It is established that the type of observed distributions (the structure elements sizes) is asymmetric. In this regard, the use of nonparametric statistics (for comparing different samples of the measurement results of structures) is effective (in particular, the Kolmogorov – Smirnov test). A joint measurement of geometry of the structures and fractures of the hard alloy revealed the identity of their structure. This directly confirms the key role of the structures in increasing of premature failure risk of constructions facing. The obtained results indicate the high efficiency of the use of computerized procedures for ranking the structures of hard alloys. The proposed procedures can also be used to describe the structures of steels and alloys.
Our study was carried out within the subsidiary agreement No.14.578.21.0129 for the financial provision (recovery) of costs, connected with applied scientific researches and experimental developments “Development of importsubstituting hard alloys with increased wear and technological properties for strengthening of wear parts of agricultural machines, used in abrasive environment”. Unique ID: RFMEFI57815X0129.

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