Good speeds for annealing steel/alloy/aluminium?

[Marp]

Hi!

What is a very high speed for annealing low carbon steel, high grade steel, stainless steel div. alloys, aluminium, ...etc

Is 100f/min for a AWG 20 NiCr alloy high ? Elongation ~ 40%
Is 100f/min for a AWG 2 copper wire high ? Elongation ~50 %
Is 1000f/min for a AWG 20 aluminium wire high ? Elongation ~20 %

Please give me some inforamtion about high speeds for a annealing process!

Thanks for your help!
MP

 

[mcguire]

Annealing is a process in which the strain energy in cold-worked metals triggers the growth of new, strain-free grains once a certain temperature is reached. The annealing temperature determines the final grain size. Time is a secondary factor. So the annealing speed you want is actually a function of your heating device in so far as it determines how long it takes to get to the temperature you want for the alloy in question.
Are you talking about continuous anneal lines, box anneal or what?

 

[Marp]

I´m talking about lines.
The annealer tube is aprox. 2m long, so the the alloy is about 7sec in the tube. Annealing temperatur is ~1100°C
So, what to you think about this ?

 

[mcguire]

MP
I don't think I can calculate what the maximum speed to anneal these wires would be for your setup. It's really more of a heat transfer problem that a materials problem.
You want to hit the recrystallization temperature at the center line of the wire as it exits the furnace.
Somebody like TVP can probably calculate that, but I would use trial and error.
Once you look up the annealing temperature for each alloy you may want to shot the temperature of the wire as it exits the furnace and adjust speed downward until you're just hitting the temperature you need.