Investigated were the structure, phase composition, triboengineering features and mechanics of plastic deformation during friction on 40Kh steel implanted with nitrogen ions under various conditions. It is shown that steel prehardening intensifies diffusive transfer of the modifying impurity into the subsurface layers at implantation temperatures 620-670 K. The utmost wear resistance of the modified steel during adhesive wear is achieved after its treatment at 670-720 K at the stages when high-nitrogen nitride ε-phases appear. When the modified layer releases low-nitrogen nitride particles γ'-Fe4N the adhesive resistance of the layer declines. A model is proposed explaining the lower wear resistance of these layers because of the disassociation of γ'-Fe4N in the spots of heat flashes. When a sufficiently thick hardened layer appears on the surface it suppresses the rotary pattern of evolution of plastic deformation in subsurface layers, thus the wear rate is strongly reduced.
|Журнал||Trenie i Iznos|
|Состояние||Опубликовано - 1 дек 2002|
ASJC Scopus subject areas
- Mechanics of Materials