Size effect for DIN 743
Full title: |
Size effect for DIN 743 |
Duration: |
07/2013 – 12/2017 |
Contributors: |
Dipl.-Ing. David Bretschneider (TU Dresden, IMM) |
Financing: |
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Objective: | Many applications of drive technology such as ship propulsions, offshore wind turbines, bucket wheel excavators and large industrial drives require load capacity calculations for shafts and axles of large diameters The objective of the project is to clarify whether the calculation of fatigue strength according to the load capacity calculations of shafts and axles (DIN 743) can be reliably transferred to components with large dimensions. |
Approach: | Hardness measurements, tensile and fatigue tests are carried out on four different materials and five raw stock up to diameters of d=500mm. Based on the results of the tensile tests, the technological size coefficient K1 is specified for the investigated materials. The results of the size factor K1 are validated by numerical-analytical calculations. Furthermore, it will be analysed whether the fatigue strength calculation depending on hardness (according to DIN 743) can be applied for components with large diameters. For this purpose, the experimental investigations on forgings with large diameters are used. The focus is set on the distribution of strength over the cross-section and the influence of inclusions on the fatigue strength. |
Results: | The project provides equations for the calculation of the size coefficient K1 under the consideration of the chemical composition of the materials. In addition, the existing methods according to DIN 743 are extended for the calculation of fatigue strength for large components. |