Best value steel for frequent thermal cycling 1

[TyCarp]

I'm over a paint line that has a conveyor which carries parts through a iron phosphate wash, an oven(220F) for 5 minutes, into the paint booth, and back through the same oven for 24 minutes. The whole cycle takes 1 hour & 45 minutes. We are in need of some new hangers which the parts are hung on. The drawings for the hangers call for AISI 4140/42 1/2" rod and AISI 4130 3/16" plate. I'm not worried about the heat from the oven mentioned above(I think? I've been wrong before). I'm worried about the heat from the oven which we use to burn off excess paint built up on the hangers. The hangers are pretty much continuously removed from the conveyor and sent to a vendor for burn off. Burn off occurs at 550 to 600F where it is then allowed to air cool and then the powdery ash is sprayed off with water. Is this the correct material for the job? Can I get away with much cheaper 1020 mild steel?

Thanks in advance!

 

[EdStainless]

I believe that the original intention was to use a hardenable steel, that had a temper temperature of 1000F. That way the burn off cycles would not impact the strength.
I don't see why you couldn't use a straight grade med C steel like 1035.
You might want to check temper embrittlement data and make sure that the hangers won't loose too much ductility.

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Plymouth Tube

 

[TyCarp]

Do you have a link to where I can find this data? Searched around and haven't come up with anything yet.

 

[swall]

We have a similar line (epoxy powder coat) and our own burn off oven. We use 1018-1020 steel for the racks. Thermal cycling is not what does them in-- just the normal wear and tear from handling that eventually bends or breaks some of them.

 

[TyCarp]

OK good to hear, that's what I was hoping. Thanks for the info.