Grain boundary

A grain boundary is a two-dimensional lattice defects in crystallography. The grain boundary separates in a crystalline regions ( crystallites or grains called ) of different orientation with otherwise the same crystal structure.

A distinction is made between small-angle grain boundaries and high angle grain boundaries.

As a large-angle grain boundary, the boundary region is referred to abut against each other in the randomly oriented crystal regions whose orientation difference exceeds an angle of 15 °. Such a grain boundary not only identifies a fault in a grain, but the grain boundary to Nachbarkristallit.

Grain boundaries can be made visible by means of chemical etching at the surface.

To gather grain boundaries or form discharges, particularly oxides.