In the department Cutting and Mechanical Surface Treatment, basic research as well as application-oriented research and development is carried out on the classical cutting production processes with geometrically determined cutting edges, such as turning, drilling and milling, and on hardening processes, such as deep rolling and shot peening.
A broad spectrum of tasks is being worked on in individual projects, bilateral projects and joint projects. In addition to the development and optimization of tools and processes, one of the core tasks is the investigation of fundamental mechanisms of action when using geometrically defined processes for machining mainly metallic high-performance materials and fiber-reinforced composite materials.
Classical machinability analyses are as much a part of the portfolio of the work as the clarification of complex questions concerning the influence of geometrically determined processes on peripheral zones. The modelling and simulation of manufacturing processes is an integral part of the work, especially in basic research. The department is equipped with state-of-the-art machine tools, powerful process measurement technology, excellently equipped laboratories and extensive computer and simulation capacities.
The work in the department of Cutting and Mechanical Surface Treatment is focused on the following technological areas:
- Hard machining
- Minimum quantity lubrication and dry machining
- high performance cutting
- Machining of difficult to machine materials, e.g. titanium and nickel-based alloys
- Machining of printed or additive manufactured workpieces
- Mechanical surface treatment
- Process development and optimization
- Tool development and optimization
- Clamping technology
In the research and development work, state-of-the-art measuring technology can be used, which allows a detailed analysis of tools, workpieces and processes. These include, among others:
- Strip light microscope: cutting edge radius measurement, tool wear measurement
- Optical microscopes: tool wear measurement, burr measurement on workpieces, chip form measurements
- Tool setting and measuring device: precise calibration of tools
- Roughness and profile measuring device: measurement of roughness and contours
- Roundness measuring device: Measurement of roundness and cylindricity
- Coordinate measuring machine: Complete recording of dimensions and shapes on tools and workpieces
- X-ray diffractometer: High-precision determination of residual stresses
- Barkhausen noise analyser: micromagnetic determination of thermal damage, hardness changes and changes in residual stress condition
- 3- and 4-component dynamometer: Determination of process forces and torques
- Rotary 4-component dynamometer: Tool-side determination of process forces and torques during milling and drilling
- High-speed camera: Optical detection of chip formation and chip removal
- Pyrometer and thermal imaging camera: measurement of process temperatures and their distribution
- High frequency power analyzer: Determination of electrical power on drives
Basic research projects aim primarily at analysing and understanding essential physical mechanisms of the manufacturing processes used through systematic studies. Frequently, the mechanisms are mapped in mathematical models in order to be able to predictively optimize manufacturing processes or shorten the optimization process in industrial practice. Different metallic materials and fibre-reinforced composites are considered in a case-specific way. Basic research is predominantly carried out in publicly funded research projects, e.g. by the German Research Foundation (DFG) or the German Federation of Industrial Research Associations (AiF).
A main research focus in the technological areas of the department is the targeted influencing of peripheral zones by geometrically determined manufacturing processes with special consideration of the achievable productivity and component quality. The effects occurring in the manufacturing process on the processed material (mechanical, thermal, chemical as well as combinations thereof) are determined metrologically and/or by simulations and their effect on the resulting marginal zone properties is systematically investigated. On the basis of these quantitative correlations, it is possible to adjust the properties of peripheral zones in a knowledge-based and thus more targeted manner than before by means of manufacturing processes.
Further questions, which are dealt with in the basic research of the department, concern the heat distribution in geometrically determined machining processes, the development and minimization of component distortion due to process- and clamping-related residual stresses as well as the interlinking of individual processes, for example for the production of drive components, in cooperation with other departments of the institute. For example, by using the finite element method in chip formation simulations, the physical causes of material changes, such as the development of residual stresses or material damage caused by process-related temperatures and stresses in the processed material, can be analysed and better understood in a more targeted manner than is often possible on the basis of measurements. In addition, analytical models are also developed in the department, which allow a better insight into the relevance of individual parameters for a manufacturing process and a faster calculation than numerical approaches.
In addition to projects in basic research, the department Cutting and Mechanical Surface Treatment is working on application-oriented research and development projects, mostly in bilateral cooperation. Among other things, the work deals with the development and optimization of tools and processes and the performance of machinability analyses. In addition, comparative analyses are also carried out within the framework of benchmarking studies.