Theoretical basis for the quantitative analysis of fracture surfaces

A theory is proposed for the determination of several basic quantities in fractographic analysis. These are the true area of a fracture surface, the surface fraction, and the volume fraction of some identifiable features intersected by a random-curvature fracture surface. The objective of this analysis is to make it possible for fractographers to take all necessary measurements on the micrographs of the analyzed fracture surfaces. It is shown that simple and exact relations can be derived when such micrographs are taken at a zero-tilt angle in the scanning electron microscope or prepared by surface replication and transmission electron microscopy. There is excellent agreement between conclusions based on the proposed theory and experimental observations.