Corrosion Resistance of Cold Worked S.S.304
Corrosion Resistance of Cold Worked S.S.304
(OP)
I know that when Non-magentic Austenitc Stainless Steel 304 is cold worked it transforms into a magnetic Martensite phase. But I want to know if this with effect the corrosion resistance of the Stainless Steel.
Any help will be appreciated.
givonz
Any help will be appreciated.
givonz





RE: Corrosion Resistance of Cold Worked S.S.304
RE: Corrosion Resistance of Cold Worked S.S.304
The corrosion resistance of stainless steel is dependent almost only on the chemistry of the exposed surface. Transformation does not alter that. Cold work can abrade the surface and change corrosion reistance, usually negatively. It can result in foreign materials to be embedded which is also hurt resistance.
But merely transforming without diffusion as with a martensitic transformation doesn't do a thing.
RE: Corrosion Resistance of Cold Worked S.S.304
RE: Corrosion Resistance of Cold Worked S.S.304
RE: Corrosion Resistance of Cold Worked S.S.304
RE: Corrosion Resistance of Cold Worked S.S.304
Pitting seems to be a necessary pre-condition for SCC. There has been endless debate over whether the mechanism is micro corrosion or hydrogen embrittlement. If austenite is more stable, SCC is less likely. If you can choose the alloy to avoid pitting you have done all you can unless you switch to the less SCC-prone duplex stainlesses.
RE: Corrosion Resistance of Cold Worked S.S.304
There are two factors governing the corrosion in SS:
1. Environment
2. Chemical composition.
If marteniste is present somehow in Austenitis SS, the corrosion resistance has to decrease in this area. Also this phase is brittle. As long as the protective oxide layer is in tact and at low pressures no effect takes place. If for any reason the protective oxide layer is removed from the martensitic region then corrosion can be rapid. Also if pressures are high the unequal elasticities of the two phase can cause break in the oxide layer and cause corrosion.
ssp
pic, kuw.