Wear resistance is always a characteristic that is strongly tied to the wear test conditions. Therefore no one can tell how this steel would behave. For example, abrasive impact wear requries good fracture toughness, sliding requires lower adhesive interaction and etc. Increasing gamma phase content would provide better fracture tougnness but higher adhesive interaction. So I would recommend first to evaluate the steel chances in the final application conditions.
If surface modification is an option in your case, plasma nitriding might be a good option. By adding nitrogen only to the surface layer of duplex stainless steel you can increase considerably the hardness and also the wear resistance. Expanded austenite is the characteristic phase change, although the ferrite grains also incorporate nitrogen and experience increased hardness. In my experience, the layer has to be relatively thin (around 5-10 microns) to keep the surface from becoming too rough. I did not had the chance to study further the wear resistance, but I did managed to create a nitrided layer of up to 120 microns with surface hardness up to 3 or 4 times that of the base material (duplex stainless steel).
The use of plasma is important here, as other nitriding methods need higher temperatures, which cause duplex stainless steels to precipitate a brittle phase in the whole volume. I wrote all about this process in my master thesis, you can see it here.
Hope it helps!
Conference Paper Low Temperature Nitriding Of Duplex Stainless Steel
Thank you for your attention.
The microstructure does not change. This process only causes carbon coating on the steel surface (specimen). The only ones experiencing hardening of the surface. Hardness figures differ according to thickness place
In case you want to increase the wear resistance of your base material duplex stainless steel it can be done as following
Aim for as high austenite % as possible by controlling Nickel and Chromium equivalents by Schoffler or Delong diagram during steel making , and strengthen and increase hardness of austenite phase by nitrogen addition.But if you want to improve wear resistance only on surface of component please go for hardfacing/plasma nitriding,HVOF coating etc.
Regards
Shivraj Singh Kasana
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