Factors Affecting the Early Stages of Corrosion-Fatigue in Commercial Aircraft Skin
Corrosion-fatigue tests were performed on tapered laboratory specimens of skin material obtained from a retired commercial aircraft. The early stages of corrosion-fatigue damage were examined in the as-received condition (with paint and clad intact), in the absence of paint, and without paint or cladding. Cracks were found to nucleate preferentially in the clad layer near prismatic pit colonies. The crack nucleation rate was affected by pH and the exposed clad/core area ratio. The growth rate of small cracks was not influenced by pH or exposed clad/core area ratio.
KeywordsZinc Fatigue Chromate
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