Surface nanocrystallization of Cu and Ta by sliding friction

Optimization of the surface structure and properties is of great concern since the failures of engineering materials such as wear, erosion and fatigue usually occur on the surface of materials. Plastic deformation from the sliding friction process has been utilized to realize surface nanocrystallization in commercial pure copper and tantalum plates in this work. The optical microscopy, transmission electron microscopy, X-ray photoelectron spectra, and uniaxial tensile testing results suggested that clean nanocrystalline surface layers of pure copper and tantalum were obtained, significantly strengthening the materials after the treatment.