Abstract
Depending on the field of operation, crankshafts are either casted or forged. The constructional transition between the crankshaft cheek and the bearing journal induces sharp notches. Due to these notches, the risk of failure under cyclic loading of the crankshaft increases. Under these conditions a failsafe dimensioning of crankshafts without any additional strengthening method is not possible. In this diploma thesis, systematic investigations regarding inducing residual stress to the crankshaft using the surface treatment technique of hammer peening are carried out. Therefore the mechanism of the hammer peening method is examined. Furthermore the process of hammer peening is implemented into a finite element simulation. The focus of the simulation is a realistic reproduction of the material behavior and the process itself. On this basis, variation studies of different parameters e.g. overlap, impact force is carried out. Afterwards, residual stresses of treated notched specimen are measured and compared with the results of the simulation. The results show, that the surface treatment process of hammer peening induces a certain amount of residual stress within the specimen. This leads to an increase of the fatigue strength. Furthermore, the material model which is used within the simulation and the calculated results are compared with the measured residual stress data and their correlation is verified.
Translated title of the contribution | Simulation of the surface treatment process of notched specimen using the hammer peening technology |
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Original language | German |
Qualification | Dipl.-Ing. |
Supervisors/Advisors |
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Award date | 28 Jun 2013 |
Publication status | Published - 2013 |
Bibliographical note
embargoed until 13-05-2018Keywords
- mechanical surface treatment
- finite element simulation
- material model
- fatigue strength