For this purpose, measurements on fatigue specimens are carried out on the steel 20MnMoNi5-5 in a service relevant heat treatment condition, in which the residual stresses are determined conventionally using an X-ray diffractometer and then the results are used in order to calibrate the µmagnetic measuring system.The surface roughness is measured
As part of the planned research project, fatigue specimens of the steels C22R and 20MnCrS5 will be subjected to conastant amplitude loading with different stress and total strain amplitudes. Within the framework of conventional fatigue tests, it is first of all not possible to make reliable statements with regard to macrocrack formation and propa
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Micro- and nanostructured hard magnetic materials and components for microtechnical applications "MiNaMag"
Permanent magnets are used in a variety of ways and increasingly in technical products, above all for data storage, in energy technology, in sensor technology, and for transport and separation processes. This large market is
For the first experiments in distilled water, a miniaturized electrochemical in-situ cell with a standard three-electrode system, which is also used in potentiodynamic polarization measurements, is being developed. The challenge here is that the cell must be sealed at the sample shafts so that cyclic loading of the specimen can occur in the cell
Following this characterization, the damaged volume is removed from the specimen, which is polished and then subjected to secondary loading on various test systems at test frequencies of 5, 60, 200 and 1000 Hz. In the HCF range, a direct comparison with the original undamaged specimens can thus be derived. In the VHCF range, possible deviations i
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Two factors in particular must be considered here. Relevant damage mechanisms can change from the HCF to the VHCF regime. For example, the crack initiation points shift into the volume in the field of defects, such as inclusions and precipitates, especially in the case of high-strength conditions. In the case of ductile materials, damag
Characterisation of materials and structures by means of scanning electron microscopy and EDX, EBSD and STEM analysis
Within the scope of a large-scale equipment application funded by the German Research Foundation (DFG), a high-resolution Clara scanning electron microscope from Tescan was purchased, featuring energy dispersive X-ray spectroscopy
Quantified evaluation of the frequency influence on the fatigue behavior of unalloyed steels for implementing in resource-efficient fatigue life prediction methods
As a part of the program of the research project, the established fatigue life prediction methods for the HCF regime at frequencies of 5 Hz will be expanded for higher frequencies (up t
Retired Professor
Prof. Dr.-Ing Joachim E. Hoffmann
Department Management WWHK
Professor and Head of Department
Prof. Priv.-Doz. Dr.-Ing. habil. Peter Starke curriculum vitae ResearchGate SciPort RLP informationbox
Associate Head of Department, Group Leader "Fatigue and Fatigue Life Calculation"
Associate Prof. Dr.-In
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Associate Head of Department
Group Leader "Fatigue and Fatigue Life Calculation"
Scientific Assistant
2025 - today Associate Professor, Associate Head of Department
2025 Doctorate (Dr.-Ing.)
2023 - 2025 Chief Engineer, Materials Science L
