Nitriding Eccentric Shafts
#1
Nitriding Eccentric Shafts
I am planning on having my irons surfaced and found a heat treating company locally that does Nitriding. After talking with him i started thinking about the benefits of having other engine internals Nitrited. I remembered a time many moons ago when i attended Continental powerplant school and the instructor was talking about the treatment of their crankshafts. He went on to say their untreated forged crankshafts had a torsional strength of 96,000lb and by just having them Ion Nitrided that their torsional strength increased to 132,000lb!!! I couldn't believe that a coating that only penetrated .003"-.005" could increase the strength of the crank but he assured me that it was true. Has anyone ever considered having their shafts Nitrided? Are there any downsides that i have not considered? It seems like a cheap alternative to buying an expensive two piece shaft.
#2
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From what I know about nitriding I don't think the nitriding alone would increase the strength that much. That said, it's done at about 900* and might offer some tempering properties during the process to already hardened steels, reducing brittleness and increasing strength. I think the e-shaft is not through hard and is only induction hardened on the journals.
Do they wear that much? Nitriding will most likely just increase wear resistance.
Somitimes the process warps piston engine cranks. Nitriding cranks used to be a big deal in piston engines. I don't know if it's done all that much any more.
Do they wear that much? Nitriding will most likely just increase wear resistance.
Somitimes the process warps piston engine cranks. Nitriding cranks used to be a big deal in piston engines. I don't know if it's done all that much any more.
#3
Most of the high end high dollar piston crankshafts are nitrided. Mazda only induction hardened the lobes of the e-shaft so the rest of the shaft is much softer. Nitriding would at least increase the surface hardness and rigidity of the entire shaft. One way or another i think i am gonna give it a try.
#4
Go for it. Ion nitriding is the also the same process used to resurface the aluminum mirrors in observatory telescopes (aside from using pure Al instead off a nitrogen source).
Here's a quick run down of nitriding processes:
http://steel.keytometals.com/Articles/Art117.htm
Here's a quick run down of nitriding processes:
http://steel.keytometals.com/Articles/Art117.htm
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#10
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I think I just broke or twisted my e-shaft and I'm considering sending the new shaft to Liberty Transmissions for their metals enhancement process (Shot peening, heat stressed relieved and cryo treated). Curious why no one mentioned this as a way to strengthen?
#14
Is there anyway to do a strength test? Like coat one als seal and have one regular seal then try to break or bend them with any kinda controlled test..
I know the als seals are the bomb, but if any developments can improve anything with our motors im down.. thanks man...
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joel(PA)
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10-04-15 06:07 PM