Bewertung von Maschinenbauteilen mit scharfen Kerben

FKM 2003
Issue No. 275
Project No. 243

Abstract:
The strength verification for components with very sharp notches is not possible, or at least not economically feasible, according to the current state of technical regulations and guidelines
Abstract:
The strength verification for components with very sharp notches is not possible, or at least not economically feasible, according to the current state of technical regulations and guidelines. However, the area of sharply notched components is becoming increasingly important in structural engineering practice. To ensure that components with sharp notches can also be calculated on the basis of the FKM guideline in the future, experimental and analytical investigations were carried out to extend the guideline for this component group. The experimental investigations comprised over 50 static tests and 38 test series with a total of approx. 470 individual tests under fatigue loading. The failure behavior of the static tests was simulated with damage-mechanical calculations based on the GURSON model. Based on the tests under fatigue loading, the approach for calculating support numbers in the fatigue strength verification of the FKM guideline was extended indefinitely into the area of sharply notched components. Parallel to the further development of the support number concept anchored in the guideline, the support number calculation was investigated with flaw models to capture the statistical size influence and implemented in a calculation program. With the samples used here, the effects of the statistical influence of size have receded into the background. For fundamental reasons, however, it is recommended that the statistical size influence be included in the FKM guideline. Further research is required for processing and broad experimental validation. Evaluation of machine components with sharp notches. Scope of report:
286 pages including 264 images, 120 tables and 7 appendices Start of work:
01.03.2000 End of work:
28.02.2003 Funding body:
BMWi/AiF No. 12380 N
Research bodies:
Technical University of Darmstadt Institute of Steel Construction and Mechanics of Materials Department of Mechanics of Materials Chairman of the working group:
Prof. Dr.-lng. T. Seeger (in charge) Chairman of the Advisory Board:
Fraunhofer-Gesellschaft e. V. Fraunhofer Institute for Mechanics of Materials IWM, Freiberg Prof. Dr.-lng. E. Sommer Dipl.-lng. M. Niessner, TU Darmstadt Prof. Dr.-lng. T. Seeger, TU Darmstadt Dr.-lng. J. Hohe, FhG-IWM Freiburg Dr.-lng. D. Siegele, FhG-IWM Freiberg Dr.-lng. H. Waltermann, Barmag AG, Remscheid Dr.-lng. E. h. J. Rabe, Rabe chstadt