anodize versus fatigue
anodize versus fatigue
(OP)
Recently there was a non-fatal crash involving an amateur built helicopter. The cause of the crash was a fatigue failure in a 0.5ODx 0.325"ID 27.9" long aluminum control tube. The tube was anodized with color to assist in building an award winning ship. It won at Oshkosh. The question is does anodizing reduce the fatigue life of aluminum? I've seen gyrocopters and helicopters with liberal use of anodized aluminum tubing and pieces.
RE: anodize versus fatigue
A quick scan of the first page returned by Googling }anodize fatigue| suggests that some effect has been documented, and the documents are available.
Mike Halloran
Pembroke Pines, FL, USA
RE: anodize versus fatigue
RE: anodize versus fatigue
Or did it fail at, e.g., a swaged end, where ex-mill cold working and the presence of threads for a rod end should also be considered?
Mike Halloran
Pembroke Pines, FL, USA
RE: anodize versus fatigue
It is possible that the above makes no sense, and you should look for confirmation from someone with more specific knowledge in this area.
jetmaker
RE: anodize versus fatigue
RE: anodize versus fatigue
Somewhere in my library I have information on the effect of nickel and cad plating on fatigue life. These effects are significant and it is often associated with the surface cracks in these coatings. I have limited information that hard anodizing (per MIL-A-8625, Type III) produces adverse effects on fatigue live, with a reduction of about 45 percent.
jetmaker
RE: anodize versus fatigue
RE: anodize versus fatigue
Aluminum / fatigue strength reduction
2024 / 30%
6061 / 60%
7075 / 17%
7178 / 65%
320 / 0%
350 / 0%
RE: anodize versus fatigue
thank you Klyde
RE: anodize versus fatigue