|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Fatigue in Materials: Fundamentals, Multiscale Modeling and Prevention
||GG-4: Experimental Investigation of Crack Initiation in FCC Materials in the High and Very High Cycle Fatigue Regime
||Thomas Straub, Michael Buck, Chris Eberl
|On-Site Speaker (Planned)
A material’s fatigue lifetime is determined by the crack formation process: damage accumulation in individual grains, micro crack initiation, short crack formation, and growth until a macroscopic crack evolves. While macroscopic crack growth and short crack evolution have been under investigation for years, crack initiation is still difficult to observe and characterize. Therefore, the focus of this work lies on the implementation of a custom built resonant fatigue setup capable of tracking damage formation. This can be achieved by sample size reduction and implementation of a sensitive resonant measurement method with results that are later correlated to small changes in the mechanical integrity of the material. HCF tests with fcc materials show a highly reproducible resonant frequency decrease correlating to damage initiation. The subsequent short crack formation can be observed optically or analyzed ex situ in an SEM. Experimental results can be used to validate lifetime prediction models.
||Planned: Publication Outside of TMS (Indicate publication title and publisher if known.)