View Single Post
  #11   Report Post  
posted to rec.boats
Jim Jim is offline
external usenet poster
 
First recorded activity by BoatBanter: Sep 2009
Posts: 160
Default NiBN coating Aluminum props

H the K wrote:
Frogwatch wrote:
On Sep 3, 11:20 am, H the K wrote:
Frogwatch wrote:
OK, here's an idea HK can help with. Last time I was at the marina at
St Marks, I was impressed by a bin full of dead aluminum props.
Actually, I was told that most could be salvaged but it prob would not
be worthwhile except for the larger ones. I asked "Why not coat Al
props with Nickel" and was told that any coating will wear off due to
cavitation and due to sand hitting it. he even showed me a prop that
had run through an oyster bar, NASTY.
However, I think the guy might be wrong. Electroless Ni adheres very
strongly. It is much harder than almost any other such coating too.
The Boron nitride electroless nickel alloys are both hard and slippery
so would resist such abrasion.
Thoughts?
Try carbonitriding. Read up on "Tenifer QPQ" Have a nice day.


Is carbonitriding done to Aluminum? I see it done to steel and in
fact measuring its thickness is one of our specialties.



Have fun:

An inductively coupled rf plasma as a medium for carbonitriding aluminum
Fayez El-Hossary, Niemat Negm, Sayed Khalil, Ahmad Abed Elrahman
(Physics Department, Faculty of Science, South Valley University, Sohag,
EGYPT), Lewis Watson (Mechanical Engineering, Strathclyde University,
Glasgow, UK)

The exceptional properties of aluminum nitride (AlN) have detained high
guarantee of advanced technological applications. An inductively coupled
rf plasma has been used to carbonitride aluminum (1050) at different
plasma conditions. X-ray photoelectron spectroscopy (XPS), X-ray
diffraction (XRD), microhardness indentation and surface microstructure
have been employed to investigate properties of the treated surface. The
thickness of the carbonitriding layer is very thin in which, the XRD
cannot detect it. However, XPS identified, after first run of sputtering
the surface, nitrogen-nitrogen and nitrogen-aluminum bonds. The
microhardness of the treated sample, at certain plasma conditions,
increases 71plasma conditions, we have studied, the temperature was high
enough to melt the Al surface and reform large grain structure with wide
grain boundaries. This form of structure could admit to the nitrogen and
carbon species to react with the bulk material through the wide grain
boundaries.


That's kind of far out science Krausie. Could you explain it to the
class. That is if you even have a clue as to what you cut and pasted. WAFA