Solution Annealing 17-4ph, how much vacuum? 1

[musashi99]

I want to solution anneal 17-4 in a vacuum. We have a spare tube furnace (6” tubes) that is used for semi conductor production. Our problem is that it is an atmosphere furnace. How much vacuum do I need to pull and maintain to avoid surface oxidation? Thanks!

 

[metengr]

Converting an atmosphere furnace into a vacuum annealing furnace is no easy task – your main concern is related to the furnace internals that can withstand buckling forces under vacuum.

The attached paper might be of interest and shows how elaborate these furnaces can be. You might be better off sending this out for vacuum heat treatment.

http://www.energy.ca.gov/process/pubs/vacuum_furnaces_tc113555.pdf

 

[MetalsInc]

Why do you want to do it in a vacuum? Can't a protective atmosphere (argon) do the trick?

 

[EdStainless]

this is a duplicate thread.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[musashi99]

Sorry for the dup. thread.

I have used argon/ hydrogen in the past on a leaky system and everything came out a nearly perfect OD green.

considering the cost to rig for a vacuum I may go back to this gas mix again. Should work better in this new furnace.

Thank you for all the replies..It is much appreciated!

Again sorry for the dup. post.