ELECTRON BACKSCATTER DIFFRACTION: A TOOL TO SOLVE DIFFERENT QUESTIONS IN THE STEEL INDUSTRY

摘要

Electron backscatter diffraction (EBSD) is a technique widely used in the field of microstructure characterisation and texture evaluation for different type of materials but mainly in the area of metals. It enables individual grain orientations, local texture, point-to-point orientation correlations and phase identification to be determined routinely on the surfaces of bulk poly-crystals. Automated EBSD enables to represent the texture and grain boundary character distribution visually and quantitatively via orientation maps. The field of material science and engineering is concerned with manipulating the microstructure of materials in order to control their properties. A good example of this is found in the area of packaging where steel or aluminium sheets are deep-drawn to form for example beverage cans. Crystallographic texture controls the performance of the can material during the deep drawing process since good or bad drawability is linked to the presence or absence of particular orientations. In order to ensure the same mechanical properties, around 20 mm of the sheets' edge are trimmed before the process continues further into the deep drawing step. However, the amount of trimming can be reduced if proper characterisation of the samples is done assessing properties such as grain size or texture. Therefore, in the first part of this talk the homogeneity in width of a cold rolled and annealed sheet will be explored using EBSD.