Postponing Crack Nucleation in 2024 Aluminium Alloy by Dynamic Precipitation from the Supersaturated State

Abstract:

Recently a novel strategy to improve the fatigue resistance of precipitation hardened aluminium alloys has been proposed, which is based on dynamic precipitation in partially aged material. In this paper, the effect of mean stress and alternative temperature treatments that can enhance the high cycle fatigue resistance through the mentioned mechanism were investigated. The material used is an under-aged 2024 aluminium alloy, which showed superior fatigue life compared to the peak aged condition. The recorded behaviour was observed to be more effective at lower stress amplitudes and lower R values. As the dynamic precipitation may not be able to keep up with the damage evolution, dedicated experiments were conducted to insert periods of controlled healing in a stress free state.

• Periodical: Advanced Materials Research (Volumes 891-892)
• Pages: 1577-1584
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.891-892.1577
• Online since: March 2014
• Authors: Meysam Mahdavi Shahri*, Rene C. Alderliesten, Sybrand van der Zwaag, Henk Schut
• Keywords: Aluminium Alloy, Dynamic Precipitation, Fatigue Resistance

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