Correlation between Scatter in Fatigue Life and Fatigue Crack Initiation Sites in Cast Aluminum Alloys 2012-01-0920
High cycle fatigue tests at a constant positive mean stress have been performed on a Al-Si-Cu cast aluminum alloy. The Random Fatigue Limit (RFL) model was employed to fit the probabilistic S-N curves based on Maximum Likelihood Estimate (MLE). Fractographic studies indicated that fatigue cracks in most specimens initiate from oxide films located at or very close to specimen surface. The RFL model was proved to be able to accurately capture the scatter in fatigue life. The cumulative density function (CDF) of fatigue life determined by RFL fit is found to be approximately equal to the complementary value of the CDF of the near-surface fatigue initiator size.
Citation: Zheng, X., Engler-Pinto, C., Su, X., Cui, H. et al., "Correlation between Scatter in Fatigue Life and Fatigue Crack Initiation Sites in Cast Aluminum Alloys," SAE Int. J. Mater. Manf. 5(1):270-276, 2012, https://doi.org/10.4271/2012-01-0920. Download Citation
Xin Zheng, Carlos Engler-Pinto, Xuming Su, Haitao Cui, Weidong Wen
Nanjing Univ. of Aero. & Astro., China, Ford Motor Co
SAE 2012 World Congress & Exhibition
SAE International Journal of Materials and Manufacturing-V121-5, SAE International Journal of Materials and Manufacturing-V121-5EJ