Modelling of constitutive and fatigue behaviour of a single-crystal nickel-base superalloy
نویسنده
چکیده
In this licentiate thesis the work done in the project KME410 will be presented. The overall objective of this project is to evaluate and develop tools for designing against fatigue in single-crystal nickel-base superalloys in gas turbines. Experiments have been done on single-crystal nickel-base superalloy specimens in order to investigate the mechanical behaviour of the material. The constitutive behaviour has been modelled and verified by simulations of the experiments. Furthermore, the microstructural degradation during long-time ageing has been investigated with respect to the component’s yield limit. The effect has been included in the constitutive model by lowering the resulting yield limit. Finally, the fatigue crack initiation of a component has been analysed and modelled by using a critical plane approach. This thesis is divided into three parts. In the first part the theoretical framework, based upon continuum mechanics, crystal plasticity and the critical plane approach, is derived. This framework is then used in the second part, which consists of three included papers. Finally, in the third part, details are presented of the used numerical procedures.
منابع مشابه
Crystal plasticity and crack initiation in a single-crystal nickel-base superalloy Modelling, evaluation and applications
In this dissertation the work done in the projects KME-410/502 will be presented. The overall objective in these projects is to evaluate and develop tools for designing against fatigue in single-crystal nickel-base superalloys in gas turbines. Experiments have been done on single-crystal nickel-base superalloy specimens in order to investigate the mechanical and fatigue behaviour of the materia...
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