Hydrogen's interaction with hardened surface layers in dry and lubricated frictional couples.

In the present work the resistance against wear of various hardened layers is analysed in exploitation's conditions which include the generation of hydrogen ions and atoms in the frictional contact as a result of tribochemical and tribothermal processes. The mentioned above analyse has been carried out on the base of experimental data obtained by simulation of exploitation's conditions in stand investigations and tribological tests. Also, it has been confirmed by the results of field wear studies of real car hanging and train brakes parts. In the light of obtained results the well-known low-friction behaviour of nitrided like layers are explained by the fenomen of 'self-lubrication with hydrogen' as well as the influence of hydrogen on the forming of oil's boundary film on nitrided surfaces is confirmed and discussed.