Abstract:

In order to deeply reveal the smoothing mechanism of roller burnishing and to overcome the difficulty in the selection of the burnishing cross feed dependent mainly upon experiences and hand feel, the roller burnishing process is taken as an issue of plane-strain mechanics and the micro-plastic deformation area is determined on the basis of the Von-Mises yield criterion and by using the Boussinesq-Flamant solution. Then, the contact pressure distribution is obtained based on the Hertz contact theory, and the stress distributions in the burnishing tool and the workpieee are respectively revealed. Moreover, by taking into consideration the surface roughness of the workpiece, some equations are established to describe the burnishing force affected by the machine tool deformation, the burnishing tool deformation, the global deformation of the workpiece, the local elastic and plastic deformation of the workpiece as well as the surface roughness deformation. The equations are further used to reveal the relationship between the roller burnishing effect and the burnishing cross feed. The validity of the adopted assumptions and the analytical equations is finally proved by a comparison between the predicted results and the experimental ones with regard to single-roller cylindrical burnishing and multiple-roller internal burnishing.

Key words: roller burnishing, precise surface machining, micro-plastic deformation, surface roughness, burnishing mechanism