strWennie1
Aerospace
I grabbed this off an hot-rod website.
It was holding a cylinder head on .. running high boost. Failure mode looks strange to me for a nut. I expect shearout of either nut or stud threads.
Reading around my only viable scenerious are ..
1) just wasn't heattreated and residual forming stresses give a hoop stress failure
2) Heat-treated and then acid bath for cleanup. The part experienced hydrogen embrittlement.
3)Manufacture used too high a heat-treatment for the material and failure is fatigue related- still would have expected thread shear.
Michael
It was holding a cylinder head on .. running high boost. Failure mode looks strange to me for a nut. I expect shearout of either nut or stud threads.
Reading around my only viable scenerious are ..
1) just wasn't heattreated and residual forming stresses give a hoop stress failure
2) Heat-treated and then acid bath for cleanup. The part experienced hydrogen embrittlement.
3)Manufacture used too high a heat-treatment for the material and failure is fatigue related- still would have expected thread shear.
Michael