Inox TP347 grain size

[alanisphoenix]

Hello, I'm talking about hot forming steel tubes.
After the heat treatment at 1060ºc, the grain size is 0-1 or 2. I need grain size between 4-7, so there are any way to solve this problem?
Ususally we have the right grain size, but when the ingots (before forging)stay too much time on the furnance (because any workshop problem) the grain size increase so much. And then we have nothing to do decreaseing it.

There are any element that we can add to the chemical composition to avoid this problem or anything after heat tretmen?

thank you so much

 

[metengr]

Alazne;
What is the material specification for this tubing? Is it under ASTM or EN or what?

How much time are you spending at 1060 deg C? This is the cause of grain growth if you are spending more time than necessary at the solution treatment temperature. You don't simply add elements to avoid grain coarsening.

 

[EdStainless]

The right way to do this is to make fine grain pipe, and then blow the grain size in post anneal. After all many specs don't allow you to process anneal this product (hot work only and call it anneal).
There is no chemistry fix for this, only correct processing.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[ijzer]

Austenitic Stainless steel grain size could be made finer by cold deformation of the material followed by a heat treatment above the recrystallisation temperature.