Abstract: A method for determining crack nucleation for a part subject to fretting fatigue. Fretting fatigue tests are performed on at least one test specimen having a material composition similar to the part. The results of the test are analyzed to determine a variation of stress intensity factor as a function of time which may be referred to as (Q{N}) for the test specimen. A relationship is then determined between (Q{N}) and crack nucleation (Ni) for the test specimen. A variation of stress intensity factor as a function of time (Q{N}) for the part is determined based on the operating conditions and loads of the part. The (Q{N}) for the part is then corresponded to the (Q{N}) for the test specimen to determine a crack nucleation value (Ni) for the part. In a preferred embodiment, a computer is programmed to conduct the analysis.

Abstract: A method for determining crack nucleation for a part subject to fretting fatigue. Fretting fatigue tests are performed on at least one test specimen having a material composition similar to the part. The results of the test are analyzed to determine a variation of stress intensity factor as a function of time which may be referred to as (Q{N}) for the test specimen. A relationship is then determined between (Q{N}) and crack nucleation (Ni) for the test specimen. A variation of stress intensity factor as a function of time (Q{N}) for the part is determined based on the operating conditions and loads of the part. The (Q{N}) for the part is then corresponded to the (Q{N}) for the test specimen to determine a crack nucleation value (Ni) for the part. In a preferred embodiment, a computer is programmed to conduct the analysis.