17-4 Corrosion
17-4 Corrosion
(OP)
We have some equipment which has corroded faster than expected and I wonder if anyone might be able to provide some insight?
Matl: 17-4PH H1150 HRC 28 with a liquid nitride treatment
Exposed to atmosphere on offshore platform in warm climate. Severely pitted/corroded within 4 months.
We have hundreds of these parts out there and several on the same platform without problems. The only thing I can think of (and I'm grasping at straws) is: Could bird droppings in a salt spray, hot & humid environment cause severe corrosion of 17-4PH?
Matl: 17-4PH H1150 HRC 28 with a liquid nitride treatment
Exposed to atmosphere on offshore platform in warm climate. Severely pitted/corroded within 4 months.
We have hundreds of these parts out there and several on the same platform without problems. The only thing I can think of (and I'm grasping at straws) is: Could bird droppings in a salt spray, hot & humid environment cause severe corrosion of 17-4PH?





RE: 17-4 Corrosion
The bird droppings would probably be in the form of phosphates, or H3PO4, or NH3/nitrates/nitrites which may go after the nitrided surface. It would be hard to do a lab test as guano isn’t available any more. If you have time I would mount a few strips near where there are a lot of droppings to monitor.
Are the components seeing any other media?
Were they liquid nitrided by the same people?
I had a fabricator substitute gas nitriding for liquid and had a total disaster
RE: 17-4 Corrosion
RE: 17-4 Corrosion
Don't you guys do any trapshooting?!