Využití metody EBSD při studiu struktury moderních kovových materkálů

Abstract

This dissertation thesis was prepared within the research project of the Regional Materials Science and Technology Center at the VSB – Technical University of Ostrava. Great attention was paid to the development of the methodology of modern methods of structural and phase analysis, in particular the method of electron backscattered diffraction (EBSD) in scanning electron microscope. The experimental part of this thesis was focused on two classes of progressive technical materials: • ultrafine-grained CP-Ti-1 after processing in ECAP die designed and constructed in the Department of Preparation of Materials, which is part of the project RMSTC. The EBSD method was used to characterize the structural parameters of the experimental material in the as-received state and after processing by 4 and 6 ECAP passes. The study of the evolution of the substructure during ECAP processing was supplemented by TEM analysis of thin metal foils. • grain oriented electrical steel (GOES) with an addition of copper, which is a significant part of the production program of ArcelorMittal Ostrava a.s. The main objective was to study the microstructural characteristics of the GOES sheets after the various production steps of AlN + Cu industrial route. The results were part of the solution of the FR–TI3–053 project with the name “Improvement of the Magnetic and the Useful Properties of the Sheets of Grain Oriented Electrical Steel”. Great attention was paid to analysis of microtexture using the EBSD technique and the study of influence of copper addition on precipitation processes of the inhibition phases during the production of GOES. Experimental results of the study of microstructure were compared with the results of simulation of a thermodynamically equilibrium state, obtained using the software Thermocalc. The results of the detailed structural analysis of these advanced materials have been interpreted in relation to the parameters of applied technological processing and the mechanical and physical properties achieved.