Hot bending Stainless steel round bar

[edward995]

Does it allow to hot bending stainless steel round bar? Is that any risk with induction heating of it?
Need to hot bend a large diameter 50mm SS304 round bar for holding down bolt . Does it need to do acid washing after that?

 

[TugboatEng]

Any discoloration of the surface reduces corrosion resistance. Acid washing will remove the discoloration.

Extended time at high temperatures can cause carbide precipitation so the bar should be quenched rapidly to reduce the formation of carbides. Stainless with the L suffix such as 304L are "less" susceptible. Stabilized alloys such as 316Ti, 347, or 348 are more resistant to carbide precipitation.

 

[EdStainless]

How hot? If you keep it below 800F you don't need to worry about sensitization (unless you keep it hot for a long time).
If you need it hotter you should go to 1950F and then bend and direct quench in water before it cools off (it should still be ablove 1850F).
If you want corrosion resistance you will need to use pickling paste to remove all heat tint.
But why are you heating it?
This bar only has a yield strength of about 40ksi, you should be bale to cold bend it with a fairly small press.

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P.E. Metallurgy, consulting work welcomed

 

[dik]

Ed, why is this? Childhood curiosity kicking in.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[EdStainless]

Rather than sensitizing it at 1200-1500 and then trying to anneal it to recover, just do the bending at the anneal temp.
If this is "L" material you could get away with something as low as 1800, but it gets riskier.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[dik]

Thanks...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

Welding an end fitting to the bar seems like less trouble.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."