Abstract
Due to continuously increasing demands of tribologically highly stressed slide faces, the investigation in technologies to produce suitable surface topographies is necessary. Depending on the application demands on surface quality and surface structure increased over the last few years. Conventional grinding processes have several disadvantages with respect to the surface structure as for example the unfavorable workpiece surface for slide faces or influence of temperature and thereby resulting transformation of the microstructure. The production of smooth and stable surfaces is realized by a honing process using an abrasive film with a slight oscillation range which is also known as microfinishing with band tools.
Typical cutting motions of microfinishing are a superposition of different tool and workpiece motions. The tangential motion is realized by a rotating workpiece while the oscillating finishing tool generates the axial motion. A force controlled infeed of the finishing tool orthogonal to the workpiece axis guarantees the contact between finishing tool and workpiece. The examined finishing process is conducted without any cooling lubricant. This is the reason for several advantages regarding ecological or efficiency aspects. Without necessity of cleaning the workpiece after the process it is possible to reduce the costs and to increase the quality of the working environment.
The machined surfaces are characterized by optical and tactile investigations. The visualized exploration shows the possibility to influence the surface roughness and the shape accuracy of the workpiece. Beside improvements regarding the surface quality it is necessary to examine the roundness and the cylindricity of the shape of workpiece. Based on a FE-Simulation the contact-situation was analyzed depending on different tool and workpiece geometries. The simulation results have been validated and verified by pressure measurement films. Thus further analysis with hardened materials lead to an improved shape of the workpiece.
An optimized shape and a low roughness are favorable for the application of tribologically highly stressed parts. Furthermore the surfaces have been characterized by specific values such as the core roughness depth Rk or the reduced peak height Rpk. A reduction of the peak roughness and waviness at same time rising material fraction leads to an improvement of the microstructure surface.
Keywords: Finishing, Microfinishing, FE-Simulation, surface structure, shape accuracy