Parkerizing surface hardness
Parkerizing surface hardness
(OP)
Hi all,
I've been through loads of Parkerizing suppliers' websites and cannot find any reference to the (Vickers) hardness of manganese phosphate surface coating. Can anyone point me in the right direction?
[I'm comparing a few different coatings on a thread that specifies MnP for corrosion and wear resistance, but I thought I'd have a look at some alternatives to see if there was anything better, as I figure that Parkerizing would be quite soft. I need to know what I am starting with in order to make a decent comparison...]
Cheers,
A.
I've been through loads of Parkerizing suppliers' websites and cannot find any reference to the (Vickers) hardness of manganese phosphate surface coating. Can anyone point me in the right direction?
[I'm comparing a few different coatings on a thread that specifies MnP for corrosion and wear resistance, but I thought I'd have a look at some alternatives to see if there was anything better, as I figure that Parkerizing would be quite soft. I need to know what I am starting with in order to make a decent comparison...]
Cheers,
A.





RE: Parkerizing surface hardness
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: Parkerizing surface hardness
We would like to help you, but as CoryPad mentioned, hardness testing of phosphate coatings is pointless. Can you provide some additional information on the application? In general, threaded fasteners are coated to reduce friction during tightening, not to provide additional hardness or wear resistance. Heat treating of fasteners provides the necessary microstructure to confer strength and wear resistance. Galling or other problems occur due to localized friction problems, not lack of wear resistance.
RE: Parkerizing surface hardness
RE: Parkerizing surface hardness
We have tested the process with titanium nitride, titanium aluminum nitride, and zirconium nitride, and with the first two coatings the corrosion resistance is comparable to that of the phosphated surface.
The surfaces coated with zirconium nitride are another story altogether. The coating itself provides substantial corrosion resistance, comparable to an oiled zinc phosphated surface. Coated/phosphated/oiled 1100 steel held up for 24 hours in ASTM B117 salt fog test with no visible rust, lasting much longer than the phosphated/oiled surface.
Jim Treglio