Analysis of cutting and wear mechanisms in brushing with abrasives of ceramics

• Applicant: Professor Dr.-Ing. Eckart Uhlmann
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 392312434

Brushing with bonded abrasives is an industrial finishing process, which is used for deburring, edge rounding, and surface treatment. The process is characterized by low process forces and temperatures. When in contact with a workpiece, the flexible abrasive filaments are deflected, which compensates for geometric inaccuracies of the tool, the workpiece, the machine system, or the path planning. Despite these advantages, the complex motion, chipping, and wear behavior limit the prediction of work results, whereby industrial process designs are mostly based on experiential values. During the first research period, the process behavior of round brushes was investigated while finishing zirconium oxide surfaces. For this purpose, experimental models were built based on finishing planar workpieces to determine the relations between tool specifications, process parameters, process forces, and work results. Subsequently, the Discrete Element Method was used to physically model the motion and contact behavior of filaments on workpiece surfaces. Tendentially, the process behavior of the brushing tools could be modeled adequately, although the physically modeled forces were lower than the experimentally determined ones. This was attributed to limited filament interactions, which in turn resulted from insufficient knowledge of the filament distribution on the brushing tool. As for the hereby applied for second research period, the previously developed methods shall be transferred to the manufacturing of defined cutting edges on cutting tools, which is assessed as of high industrial relevance due to appropriately prepared cutting edges increasing productivity and tool life. Therefore, an experimental database is built based on technological investigations with ceramic cutting inserts. To improve the physical process models, filament distributions are determined with an image-guided approach to characterize the utilized brushing tools geometrically. In addition, wear models are implemented to physically model the material removal at the cutting edge. Hence, the main goal of the second research period shall be the knowledge gain regarding brushing with bonded abrasives of ceramic cutting edges based on physical process modeling.

• DFG Programme: Research Grants