Which heat-treatment should be applied to 316L austenitic stainless steel in order to reduce or remove the defects after plastic deformation without recrystallization?
Hi Oksana, you could use an as-received 316L steel in which plastic shear bands (or mechanical twins), dislocations and other defects are almost absent. Alternatively, you could heat the cold-worked steel up to a few hundred degrees (e.g. 500C, 600C or others) with some holding durations (from 10 min to 2h) to anneal the microstructure. You may consider to do some annealing experiments to find out the best heat treatment parameters you want.
Dear Oksana Klok,
Recovery is the term used to describe the decrease of elastic energy via rearrangement and annihilation of the dislocations that have introduced by cold deformation. The recovery temperature, Trec, is about equal to 0.3 Tm where Tm is the melting point in Kelvin. On recovery, the morphology of the metal grains does not change. In case of stainless steel 316L the recovery temperature is in the region of 510 K , corresponding to about 240 oC. At higher temperatures recrystallization may play a part. My question is: what is the reason to avoid recrystallization?
See page 69 of the attached link.
http://www.delftacademicpress.nl/m017.php
Hi Oksana,
If you do the solution annealing treatment at 1050°C for 30' and then quenched in water, the prior austenite grain size is not modified significantly and the CW should be removed. Besides, this heat treatment prevents the formation of any carbide in the grain boundaries (they are dissolved at those temperatures) which might be a concern for SCC studies (I believe this is your case). Below 300°C, you might have stress relief but I doubt that you can recover the micro-structure in a short period of time (
Hi Oksana,
You can make a solution treatment at 1050°C for 30 for complete dissolution of all carbieds and then quenched in water, the prior austenite grain size is not modified significantly and the CW should be removed. Besides, this heat treatment prevents the formation of any carbide in the grain boundaries (austenitization phases at 900) (they are dissolved at those temperatures). You can also apply treatment below 300°C, you might have stress relief but I doubt that you can recover the micro-structure in a short period of time less than 1h. Anyway, it always depends of what you want to do after and i think many expriments should be done for the best properties .
Best regards,
Ahmed Algendy
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering