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Passivating Iron (1 Viewer)
- Thread starter wrxsti
- Start date
doesn't seem possible...
passivating metal is one which forms an impervious oxide layer on the surface upon oxidation... iron is itself an active metal... unless you mean cathodic protection (using sacrificial anode or supplied voltage) or surface alloy (make a stainless steel surface)
passivating metal is one which forms an impervious oxide layer on the surface upon oxidation... iron is itself an active metal... unless you mean cathodic protection (using sacrificial anode or supplied voltage) or surface alloy (make a stainless steel surface)
It is possible, acording to the book. I'll just quote it
"Passivate the iron - Although iron does not self-passivate as aluminium or chromium does, it is possible to form chemically a relatively inert surface layer. Special rust-preventing paints often contain potassium chromate which oxidises surface iron atoms intoa relatively impervious layer. Phosphoric acids, present in many rust converters or inhibitors, forms iron(III) phosphate which is very insoluble and bonds tightly to the surface. Such passivation is often done before painting steel objects, because it improves the protection offered by the paint"
I'm not sure if this answers the OP's question, but I guess that these methods stop the oxidation layer from being porous and therefore stop corrosion?
"Passivate the iron - Although iron does not self-passivate as aluminium or chromium does, it is possible to form chemically a relatively inert surface layer. Special rust-preventing paints often contain potassium chromate which oxidises surface iron atoms intoa relatively impervious layer. Phosphoric acids, present in many rust converters or inhibitors, forms iron(III) phosphate which is very insoluble and bonds tightly to the surface. Such passivation is often done before painting steel objects, because it improves the protection offered by the paint"
I'm not sure if this answers the OP's question, but I guess that these methods stop the oxidation layer from being porous and therefore stop corrosion?