Short answer - NO, not acceptable.
Planishing may be ok for a lightly sand eroded surface, but if there is a divot, then no, the depth of that divot still remains and rubbing it with a steel rod will simply "smear" the surface material over it. The stress concentration will remain.
My experience is with steel. High strength steel fatigue strength can be plotted against surface finish. Rougher is lower. I had an injector tip (25ksi pressure) that was failing due to fatigue, but the surface finish was within spec. We found that the surface finish was altered during heat treat, and that the finish of the post machined part was the controlling factor. The peaks of the asperities were burned off but valleys remained.
I have no data on aluminum, but this experience would say not following the book is very risky.
__________________
Bill
RV-7
Lord Kelvin:
“I often say that when you can measure what you are speaking about,
and express it in numbers, you know something about it; but when you
cannot measure it, when you cannot express it in numbers, your knowledge
is of a meager and unsatisfactory kind.”
|
Linear Mode
