We've found regular industrial hard chrome thinner than .002" without undercoating offers little or no corrosion protection for immersion-corrosion. Thicker layers (.005" - .010") work alot better if you can afford it. The micro-cracks present in typical IHC don't go that deep, so it eliminates...
Thanks Kenvlach, we have both of those amendments, what I speak of is apparenlty called "Interim Change 1 to Amendment 2 of QQ-N-281D". Our information handing service has never even heard of it, but our customer is supposed to be getting it for us.
On the bright side it looks like a decent...
I'm wondering how a 0.05% decrease in carbon content would beneficially affect the properties of Monel 400. I realize carbon additions generally increase strength while decresing ductility, but somehow I doubt the reason for lower carbon in the situation below has anything to do with improving...
Hello All,
I'm looking for any comments/suggestions/advice on hardfacing Nickel Aluminum Bronze (UNS C95800) with Stellite grade 21. This is in a valve seat application with difficult access to the seating surface.
Does anyone know of this base/filler combo being done before? If its possible...
Chemistry and microstructure tests came back OK. Carbon, Silicon, and Phosphorous are within the limits of ASTM A395. Metallography showed no evidence of dross, inclusions, microshrinkage or poor nodularity. The sample's matrix was as expected for the annealed condition.
Turns out that the...
EdStainless,
Yes, we have a few possible solutions that involve spreading the load more... design change is one, adding more gaskets is another. For now, stoning the face flat and re-assembling seems to stop the problem. (we were getting leakage because the raised areas were preventing proper...
Thanks
They are allowing us to remove a small 1/4" sample & send out for metallography and chemical analysis. Although a full yield test would be preferable, hopefully microstructure and chemistry will say what (if anything) is going on.
I'll post conclusive results if/when we get them.
Metengr,
Destructive testing is not an option - raised areas on castings are being stoned down by hand and machinery is being re-built using original parts. (very time critical application, but failure would not be dangerous)
Determination of raised areas was done by dyechem transfer in the...
Hello All, I'm wondering if anyone knows of a weakening mechanism that could lower the yield strength of 60-45-15 Ductile Iron by more than half without making it overly brittle.
We have several large (100-500lb) ductile iron castings that are displaying a small amount of plastic flow at an...
Yes, I have the same values for NAB.
Thanks for the references, they have already helped alot. I had been working off of an old revision of 889 without the notice 3 chart and was finding it to be a bit sparse.
So it sounds like I should be comparing corrosion resistance when trying to...
I've been searching for good numbers on the electrode potential of 2205 duplex stainless, but keep comming up dry. Conditions/specifics are:
Flowing Seawater (8-13 fps)
50 to 80 degrees F
Sat. Calomel reference electrode
I've found one reference to it in these forums as being "between that of...
