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Calculating loss of fatigue strength after hard anodising

I need information on the effect of hard anodising on the fatigue properties of the aluminium alloy substrate up to 0.005 ins. BELOW the hard anodising layer. I am aware that the fatigue strength of the substrate is reduced but does it recover if the hard anodising is chemically (or mechanically) removed.

Thomas Bruce
Aircraft Manufacturer - Yeovil, Somerset, England
2003

The fatigue strength of anodized components is reduced because the hard oxide coating is brittle, and cracks initiate quickly. These cracks then propagate through the anodized layer and into the substrate. If you can permanently remove the effects of the anodic treatment, without introducing additional problems (overheating, machining gouges/cracks, etc.), then you should be able to restore the fatigue strength to that of the base metal.

Toby Padfield
Automotive supplier - Michigan
2003