What is the difference between intergranular and transgranua

What is the difference between intergranular and transgranuar fractures?

Solution

(A) Intergranular Fracture is a fracture that follows the grains of the material, where cracks that take place along the grain boundary. In a wall of bricks it would correspond to a fracture that takes place in the mortar that keep together bricks. In metals with multiple lattice organizations, when one lattice ends and another begins, the fracture changes direction to follow the new grain. This results in a fairly jagged looking fracture with straight edges of the grain and shiny surface may be seen.

There are several processes that can lead to intergranular fracture.

(B) Transgranular fracture is a fracture that follows the edges of lattices in a granular material, ignoring the grains in the individual lattices. The results in a fairly smooth looking fracture with less sharp edges than one that follows the changing grains. This can be visualized as several wooden jigsaw puzzle pieces with the grains showing, but with each piece having grains running in a different direction. A transgranular fracture follows the grains in the wood, not the edges of the puzzle pieces.