Friction nitriding of iron alloys

Changes in the structure of the surface which occur during heating by friction in ammonia connected with a strongly dispersed grain structure and an increase in the extent of grain boundarires created by the high density of constantly moving and interacting crystal structure defects (vacancies, dislocations, disclinations) leads to intensification of the impregnation process, an increase in nitrogen concentration in the layer, and as a consequence of this to marked hardening and also an increase in the wear and corrosion resistance.