comparison microstructure at different fracture areas

From my memory, you need a whole chapter of the book to fully explain the different due to material compositions, type of fractures and type of heat treatment, so it would be easier if you can get the info from the book and post the specific question

Cheers

Need a better description of the question or fracture cause.

If the entire part is the same microstructure, and the fracture is like a charpy or izod, test, then the microstructure will be whatever it is. however, the fracture appearance will be either brittle or ductile...

If the fracture is caused by an inservice failure, then there may in fact be a difference in microstructure depending on conditions leading up to failure.

I often see decarb, for instance, along a seam that is the nucleation for a fracture.

The type of failure and the type of microstructure are key pieces of info needed to answer what we think your question is. milo