Abstract
Electron backscattered diffraction (EBSD) is performed with the scanning electron microscope (SEM) to provide a wide range of analytical data ranging from crystallographic orientation studies, to phase identification to grain size measurements. The specimen’s plane of polish is oriented at a steep angle, about 72°, to horizontal. While a diffraction pattern can be obtained in less than a second, image quality is improved by utilizing a longer scan time. Grain mapping, however, requires development of diffraction patterns at each pixel in the field and is a much slower process. The quality of the diffraction pattern, which influences the confidence of the indexing of the diffraction pattern, depends upon removal of damage in the lattice due to specimen preparation. Some researchers claim that removal of this damage can only be obtained using electrolytic polishing. This text, however, demonstrates that the use of modern mechanical preparation methods, equipment and consumables does yield excellent quality diffraction patterns without use of dangerous electrolytes and the problems associated with electropolishing. Basically, if mechanical preparation results in quality polarized light images of non-cubic crystal structure elements and alloys (e.g., Sb, Be, Hf, α-Ti, Zn, Zr), or color tint etching of cubic, or non-cubic crystal structure elements or alloys produces high-quality color images, then the surface is free of harmful residual preparation damage and EBSD patterns with high pattern quality indexes will be obtained.
