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Information × Registration Number 0215U009416, 0113U000306 , R & D reports Title Determination by methods of speckle metrology and interferometry of deformation characteristics of materials to estimate parameters of their corruption subject to local fields of plasto-elastic condition popup.stage_title Head Muravsky Leonid, Доктор технічних наук Registration Date 20-01-2016 Organization Karpenko Physico-Mechanical Institute of the National Academy of Science of Ukraine popup.description2 The review of interferometric methods of research of materials and wares has been made for the last 30 years. The method of twowave two-step interferometry is developed with the arbitrary change of phase of reference beam for the reconstruction of relief of rough surface. On the basis of method of twowave two-step interferometry with the arbitrary change of phase the new method of determination of geometrical parameters of tireless area of pre-destruction is developed in models with the stress concentrators at the cyclic loadings, using the parameters of roughness of micro- and nanorelief of surface. On the basis of method of twowave two-step interferometry with the arbitrary change of phase the new approach is offered of determination of geometrical parameters of initial microflaws which arise up on-the-spot carbon steels as a result of their co-operating with hydrogen. Kinetics of change of relief the surface of material is investigated as a result of hydrogen desorption from it. Executed work on development of method of evaluation of exactness of the high-precise speckle-correlation system of analysis of the tensely-deformed state of material in the vinicity of top of crack on the basis of presentation of the fields of tensions by the Williams series. The constituents of errors of the certain fields of tensions, casual constituents of errors of certain coefficients of Williams series, are set, co-ordinates of top of crack. Offered and described chart of registration and algorithm of treatment of speckle patterns for the estimation of spatial sizes of plastic area on a change the roughness of surface on the basis of comparison of auto-correlation functions. Experimental approbation and comparing of algorithm is conducted to the analogical method of treatment during research of mechanisms of tireless destruction of compact standards of construction materials. The errors of some known rapid algorithms, in-use for subpixel combination of images together with the method of cross-correlation in a frequency plane are analysed. The conducted analysis rotined that the errors of the considered algorithms depended on texture of entrance images and form of peak of cross-correlation. Using property of symmetry of cross-correlation peak, which is observed at small displacements of similar images, a new rapid algorithm is offered for subpixel combination of images. For establishment of systematic error of algorithm the sequence of test images is created with the set subpixel displacement, using which, the systematic and casual errors of the offered algorithm are estimated. Using the method of digital correlation of images, the algorithm of determination of the module of resiliency is offered at a bend and conducted his experimental approbation. For the increase of exactness of the offered algorithm, for determination of radius of curvature of beam standard a least-squares method is used for approximation of experimental information. The offered algorithm includes procedure of calibration of the optical system, which allowed to decrease influence of geometrical distortion on exactness of the got results, also. On the basis of research of aluminium alloy of D16 and high-quality low-carbon steel 20 became results, touching the substantial changes of amplitude of resilient hysteresis, remaining deformations and Young modulus depending on the state of these materials (after their heat treatment), capable to become a base for creation of expressmethod of estimation of imperfectness of structure of metals without the leadthrough of labour intensive structural researches, and also estimation of their standard mechanical descriptions and cyclic longevity, are got. It is rotined in particular, that the developed method is also a sensible instrument for the study of hydrogen degradation of metals. Product Description popup.authors Ільчишин Богдан Дмитрович Беген Іванна Михайлівна Вороняк Тарас Іванович Гаськевич Георгій Ігорович Голинський Іван Стахович Дем'янишин Наталія Михайлівна Дрималик Андрій Романович Кметь Аркадій Борисович Кость Ярослав Павлович Кулик Ігор Іванович Куць Олександр Григорович Личак Олег Васильович Максименко Олександр Парфенович Мицик Богдан Григорович Половинко Тарас Ігорович Сахарук Олександр Миколайович Франкевич Людмила Франківна Штабський Микола Кірович popup.nrat_date 2020-04-02 Close