Methodology for Revealing the Phases and Microstructural Constituents of the CMSX-4 Nickel-Based Superalloy Implicating Their Computer-Aided Detection for Image Analysis

Abstract

The paper presents the findings of a research on the selection of methodology for revealing the microstructure in metallographic investigations on the example of the single-crystalline CMSX-4 nickel-based superalloy. A set of chemical and electrochemical methods of etching has been selected. The metallographic specimens from the analyzed material have been treated with the etchants. After every etching procedure, microphotographs of the microstructure were taken by means of an optical microscope and a scanning electron microscope. Both useful and disadvantageous effects of etching with the respective etchants have been displayed. The etchant application for a qualitative and quantitative analysis has been considered on the basis of the enclosed microphotographs. As a result, examples of a computer-aided detection of the phases and microstructural constituents present in the analyzed CMSX-4 alloy for the selected revealing methodologies have been demonstrated. The described investigations enable a better understanding of the essence of the selection of the microstructure revealing methodology and its influence on the obtained results.

A machine learning approach to map crystal orientation by optical microscopy

“…The working principle of DRM is based on measuring and analyzing the reflection of light from the surface of the material as a function of the illumination direction [10][11][12] . When the material is chemically etched, the preferential dissolution of specific crystallographic planes [13][14][15] or phases 16 can generate topographical surface features which are linked to crystallographic orientation. These features reflect visible light preferentially at certain angles, producing a directional (i.e., anisotropic) reflectance effect.…”