Ceramic Densification of Chrome

[Stephen Booth]

I have a few customers interested in the Ceramic Densification of Chrome platting. Several companies do this process in the USA, Australia, and Japan. If I understand correctly this techique, the part is chrome plated, then a two layered coating is applyed in slurry form. Then heated at low temperature, I believe less than 200C, the coatings can be as thin as 3 to 7 micron.

Question
Is this material commercially available, and who is the supplier?

[Gordon]

Hi Stephen

Not much experience with this type of coating I'm afraid. I assume this treatment is primarily to seal micro-cracks in hard chromium plating as a posed to providing a coating. The conformal type ceramic coating processes appear mainly as proprietary processes, like the "Monitox" coating. These can also be used for sealing thermal spray coatings, particularly for high temperature service where organic sealers fail. I know Aremco (http://www.aremco.com) did market some ceramic sealers, so may be worth speaking to them.

[KevinT]

Stephen,

The densificaton of Chrome Plate is a very common process and is offerred By Bodycote KTECH in the UK, North America, SIngapore and Dubai.

The trade name is TECH 17. This is a chrome oxide based slurry that is applied to the Chrome plate. Caplillary action draws the slurry into porosity and cracks thus sealing the chrome. Subsequent firing thermochemically reduces this slurry to a ceramic bonding to the substrate and the chrome Plate. This prevents any corrosive environment from undermining the chrome plate and spalling the plating.

Gordon is also correct that this coating can and does seal HVOF Tungsten carbide as well as other other coatings that have inherent porosity or a propensity for cracking.

Hope this helps

[Gordon]

Hi Kevin

to the Surface Engineering Forum.

[KevinT]

(03-10-2009 03:15 PM)Gordon Wrote:  Hi Kevin

to the Surface Engineering Forum.

Thank you Gordon,
A huge salute to you and this forum. I have been looking for this type of venue for a long time, and thanks to you and your members, This is terrific.

Kevin

[sorousheti]

Hi every one
I want more information about thermal spray sealers especially WC-Co sealers.
I read all of comment and now i want to know what is the composition of tech 17? is this aluminum filled phosphate bonded?
Please help me
Thank you
sorousheti