How to Determine Consumed Fatigue Life in Cast Aluminum Parts?

[rikcardo]

How to determine in a cast aluminum part its consumed fatigue life?

Lets imagine I get a cast aluminum part that looks good, but I have no idea for how many km it has been used (automotive). Which kind of non destructive tests or methods could I use to determine the consumed fatigue life, and that way know if it should be replaced?

I can only compare to a new part, I have no other information whatsoever.

Help would be great appreciated :)

best regards

R.

 

[rikcardo]

complicated topic I see :) no one?

 

[nucleus]

I don’t know how you would determine the “consumed fatigue life,” whatever that is. Fatique cracks take time to develop and can be picked up with an inspection program using liquid penetrant inspection (LPI) or eddy current inspection.

http://en.wikipedia.org/wiki/Dye_penetrant_inspection

 

[rikcardo]

But what I would like to know is how close am I from having a crack. There are no symptoms in the material? There material does not change somehow during cycling before cracking?