A PRACTICAL INVESTIGATION INTO IDENTIFYING AND DIFFERENTIATING PHASES IN STEEL USING ELECTRON BACKSCATTER DIFFRACTION

摘要

While Electron Backscatter Diffraction (EBSD) has been proven useful for differentiating phases in steels such as austenite from ferrite, other constituent phases such as bainite, martensite, cementite and pearlite are considerably more difficult. Often these difficulties arise due to similarity in the crystallographic structure between constituent phases. For example, martensite is body-centered tetragonal. However, it typically has a c/a ratio of approximately 1.04 but varies depending on carbon content. This is very close to a standard body-centered cubic structure, making it difficult to distinguish martensite from ferrite based on analysis of individual EBSD patterns. This work explores different EBSD image quality based approaches to differentiating separate steel phase structures.