USING METHODS OF THE SCANNING ELECTRON MICROSCOPY FOR METALLOGRAPHY RAIL STEELS

Receipt date: 
14.09.2017
Section: 
Year: 
2017
Journal number: 
УДК: 
625.143.2, 620.18
DOI: 

10.26731/1813-9108.2017.4(56).189-196

Article File: 
Pages: 
189
196
Abstract: 

Traditional research methods are not enough to identify the imperfections of technological processes in the smelting of rail steel and the subsequent production of rails in modern conditions. The purpose of this article is to demonstrate the possibilities of applying a combination of traditional, standardized methods of analysis of metals and modern methods of the material analysis such as scanning electron microscopy (hereafter SEM), x-ray microanalysis, measurement of amplitude of the Barkhausen noise, residual stresses for the search of defects, material structure analysis with the aim of improving production technology. A scanning electron microscope JEOL JIB-Z4500, equipped with an attachment for energy dispersive analysis, an installation for determining the residual stresses; a digital analyser Rollscan 300 for measuring the amplitude of the Barkhausen noise together with an optical microscope MET-2, and cutting and grinding machines to prepare samples for metallographic studies were used for the analysis. The changes of the magnetoelastic parameter in the different plot defined the presence of structural defects and cracks in the surface layer of the sample. The investigation of the microstructure on metallographic microscope MET-2 allowed establishing the phase comprising the sample, and a study by SEM methods made it possible to confirm this and accurately measure the score of the lamellar perlite. Also, the method of SEM and x-ray microanalysis helped to determine the nature and composition of the nonmetallic inclusions, to show the distribution of elements on the surface of the microsection. Thus, the combination of traditional metallographic, mechanical and new research methods that complement and clarify the requirements of GOST R 51685-2013 may allow rapid and accurate analyses of the compliance of rail steels Standards, as well as determining the causes of the destruction of rails, and inconsistencies in processes.

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