\b[<Ferrite> etches faster in <Nital>], so it recedes and leaves <cementite> standing as the higher ridges. The identification is based on the surface-relief preparation, not on assuming that every bright feature in every microscopy mode is <cementite>. In the stated AFM image, brightness is a displayed height contrast.

Solution

Past exam of the materials science course of the University of Cambridge / 2018 / Paper 1 / 4 / b / iv / Solution

 Solution (source code)