Subsequent diamond slide burnishing with superhard materials on high-precision milling surfaces for manufacturing optical-functional components

• Applicant: Professor Dr.-Ing. Eckart Uhlmann
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 572396442

The machining of technical surfaces is mainly determined by the feed rate f, the cutting speed vc and the tool geometry. This results in the use of adapted process parameters with low feed rates f for the machining of components with high demands on surface roughness. This considerably reduces the economic efficiency. A possible finishing of the surfaces can be done by diamond slide burnishing, which is a forming process according to DIN 8583 5. A solid body of a hard material (superhard material) is pressed onto or into the surface of a workpiece with a defined process force FPr. At a defined feed rate vf, the diamond slide burnishing tool head slides over the surface of the workpiece. The frictional state prevailing in this process corresponds to the sliding friction µG. By plastic deformation of the near-surface structures, the surface roughness can be reduced and the residual stress condition can be favorably influenced. Furthermore, diamond slide burnishing has so far only been used for finishing rotationally symmetrical workpieces on lathes. However, it shows great potential for the finishing of milled parts. Therefore, the aim of this investigation is to create a knowledge base for translational diamond slide burnishing with MCD spheres on high precision milling machines (HP milling machines). In order to achieve the main aim, two work packages (AP) will be implemented in the first funding period. AP 1 contains the investigation of the influence of process variables and workpiece properties on single line as well as multiline translatory diamond slide burnished surfaces in order to gain insights into the influence of the process variables and their interactions. Accompanying in AP 2 process models for the description and simulation of the forming process during the diamond slide burnishing process are to be developed. The material to be processed is a steel produced by powder metallurgy. The target values to be investigated are the achievable surface roughness of the workpiece, the hardness according to Vickers HV, the residual stresses σE in the workpiece, the tool wear ΔWZ as well as the acting process forces FPr. As a result of the project, fundamental scientific findings on translational diamond slide burnishing with MCD spheres are available, which are suitable for the production of components with arithmetic mean deviation values of Ra ≤ 20 nm on HP milling machines.

• DFG Programme: Research Grants