Formation of Nanocrystallized Structure in Worn Surface Layer of T10 Steel against 20CrMnTi Steel during Dry Rubbing

T10 steel slid against 20CrMnTi steel on a pin-on-disc wear test rig. Optical Microscope (OM), scanning electron microscope (SEM), and High Resolution Transmission Electron Microscope (HRTEM) methods were used to analyze the microstructures in the worn surface layers. The microstructures in the worn surface layers of pins and discs were all severely plastically deformed. Furthermore, the ultrafine and even nanoferrite structure (10 nm to 100 nm) was observed when the normal load reached 60 N. The mechanism of forming nanocrystalline structure in the sliding friction induced deformation layer (SFIDL) was elucidated as the result of the simultaneous and recursive actions of (i) severe shear deformation and (ii) friction heat on the contact surface.