Effect of spatial orientation of toroidal roller on stress-strain state of cylindrical blank

The purpose of this work is to determine the stress-strain state of the surface layer of a cylindrical workpiece under the influence of a toroidal roller. The novelty of the research is the question of the influence of the spatial orientation of the working tool on the stress-strain state in the source of plastic deformation and residual stresses in hardened parts. Spatial orientation refers to the inclination of the roller axis to the axis of the cylindrical workpiece in the horizontal plane and the rotation of the roller axis relative to the workpiece axis in the vertical plane. The problem was solved because of finite element modeling using the ANSYS computer program. The stress-strain state under the influence of a toroidal roller on a cylindrical workpiece was assessed by the magnitude of temporary stresses arising in the deformation zone, residual stresses after unloading the hardened workpiece and the depth of the hardened layer. It has been established that the greatest temporary and residual compressive stresses are formed at an angle of inclination of the toroidal roller equal to 45°. Subsequent increases in this angle of inclination lead to a decrease in the stress state. The rotation angle of the toroidal roller axis also has a positive effect on increasing the stressed state of the hardened layer. The angle should also not exceed 45°, since a subsequent increase leads to an increase in the stress state, which negatively affects both residual stresses (σi > σт) and temporary stresses (σi > σв). The maximum depth of the strengthened layer is also formed at an inclination angle of 45°, and at a rotation angle of the roller axis it also increases at values greater than 45°, but in this mode, the material reaches its ultimate strength.