AISI 316L annealed and cold drawn

[Brnic]

Hello,

I have carried out uniaxial tensile tests of AISI 316L stainless steel (annelead, cold drawn) at elevated temperatures. Corresponding curves (yield strength 0.2% and ultimate tensile strtength vs. temperature) are given in the attachemnt.
I am trying to explain what is happening with yield strength 0.2% at temperatures between 350-400. What is causing the sudden drop in this curve?

Many thanks
Regards
Brnic

 

[EdStainless]

What was your stress relief temperature prior to testing? How long were the samples held at temp prior to testing?
My hunch is that strain relief kicked in.

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Plymouth Tube

 

[limey1]

annealed, then cold drawn? Am I missing a step or was the material stress relieved?