Ernest;
I agree that the geometry of the geometry of the cuts is certainly not ideal; and if it were 321SS or similar; yes, I’d expect it would it to disintegrate in about 50 hrs or less. But inconel is very corrosion resistant and very strong up to 2000+F. There will be some self-annealing of the stresses at 1700F. It would be interesting to know what temp it actually gets to because there is some expansion cooling of the gases in the muffler.
Also it is very tough stuff – trying to drill or file inconel will just wear out the tools. Holes have to be punched, cut with water jet, or some other technique.
It will be interesting to see how it stands up; but I think it has a good chance to prove to be quite durable.
Al
A grinder will leave two fairly severe 90 degree corners on every edge
of the cut slot. Compounding this is the fact that the side grinder
cuts a circle. The end of each slot will be left with a knife edge
profile pointing back toward the slot. This will create some mean
stress risers. The expectation is that this tube is to live in an
environment that has to be the closest thing to hell on Earth we could
imagine (extreme heat and constant sonic blasts).
I would have suggested drilling 3/16" holes and connecting them with the
grinder. Unless the inside tube is fabricated different than what I
understand, I can't help but to think that it will have a very short
life. Cracks will start in the corners of each slot, and the tube will
disintegrate. Can it be easily pulled apart so that you could run a
round needle file down both sides of all the slots to round them out?
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