The part is mounted in a resin puck. A process of grinding, polishing and sometimes chemical etching is used to view the subsurface in steps.
This is a destructive process – the part is destroyed in the process of the analysis.
An example of a white etching crack found subsurface is shown below:
An example of a white etching crack network around a spall is shown below:
Some examples of a micropitted surface as viewed by sectioning are shown below: