Sensitivity of Nickel-Aluminum bronze against material defects and environmental influences in the very high cycle fatigue regime
Abstract
Due to their very good mechanical properties and their outstanding chemical resistance to seawater, nickel aluminum bronzes are interesting materials for load-bearing structures in the maritime sector. Components made of these alloys can be produced in their final form using additive manufacturing processes. However, additive processes can lead to the introduction of material defects and to a locally unfavorable microstructure, which impairs the mechanical strength and, in particular, the fatigue strength of the component. The main scope of the intended research cooperation is the quantification of the relationship between microstructural parameters (grain size, grain orientation, crystal plane misorientation and secondary phases) and fatigue strength, in particular the growth of microstructural short fatigue cracks in additively manufactured nickel aluminum bronzes in heat treated and non-heat treated condition. Fatigue tests at very high numbers of load cycles are to be carried out at ultrasonic frequency. For this purpose, an experimental setup is to be developed that enables in-situ investigations of fatigue crack growth. The aim is to find fundamental relationships between the local microstructure and the crack growth rate. The local crystal structure and any secondary phases present at the crack tip are correlated with the loading and the crack propagation and described in suitable models. Crack growth is observed both from natural defects and from precisely defined notches introduced using a focused ion beam or mechanically.
- Material fatigue
- Ultrasonic technique
Project staff
Herwig Mayer
Ao.Univ.Prof. Dipl.-Ing. Dr. Herwig Mayer
herwig.mayer@boku.ac.at
Tel: +43 1 47654-89202
Project Leader
01.07.2022 - 30.06.2025
Michael Fitzka
Mag.rer.nat. Dr.nat.techn. Michael Fitzka
michael.fitzka@boku.ac.at
Tel: +43 1 47654-89203
Project Staff
01.07.2022 - 30.06.2025