Holistic tool modification for twist drill deep hole drilling with high thermal tool loads

• Applicant: Professor Dr.-Ing. Dirk Biermann
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560349284

High-performance components that are exposed to high mechanical and thermal loads, are used in aggressive environments or have to meet lightweight construction requirements. The applications range from turbine and compressor components in the energy sector to the chemical industry and components in automotive engineering, aviation and general mechanical engineering and place high demands on the materials to be used. Materials such as the nickel-based alloy Inconel 718 or the titanium alloy Ti6Al4V meet these requirements, but are difficult to machine due to the high thermal and mechanical tool loads and generate high tool wear and low productivity. The forces and temperatures during machining also have an effect on the surface integrity, which can have a negative impact on the application behavior of the components. As part of the previous project “Investigations on optimization of the cutting edge of twist drills for the machining of the high temperature resistant nickel base alloy Inconel 718”, the thermal tool load on short spiral drills was significantly reduced by a holistic, mechanically and fluidically optimized design of the flank face and guide chamfers. The aim of this transfer project is therefore to transfer the knowledge gained from short twist drills to twist drill deep hole drilling tools for the production of holes with high length-to-diameter ratios. Deep hole drilling tools are not only subject to high thermal loads due to the longer continuous cutting-edge engagement, the geometry in the area of the guide chamfers is also an essential feature for the guidance of the tool and thus for the center runout. The question of how the advantages of tool modification can be transferred to deep hole drilling without negative influences is also focused on the influence of the lubricoolant strategy with the analysis of emulsion and deep hole drilling oil. In addition to the analysis of the application behavior, a reliable implementation of the grinding process for the production of these long and thin tools is of decisive importance for the industrial use of the tool modifications. With the support of the companies Gühring KG, Schütte Schleiftechnik GmbH and Molemab GmbH, industrial expertise from the fields of tool manufacture, grinding machines and abrasives is therefore being incorporated into the project.

• DFG Programme: Research Grants (Transfer Project)
• Application Partner: Gühring KG; Molemab GmbH; Schütte Schleiftechnik GmbH