Dear friends,
Anybody can help me to get the physical properties ( Thermal conductivity, Young's Modulus, Poisson's ratio, Coefficient of thermal expansion) of Nikasil coating normally coated for engine cylinders.
Regards
pat pprimmer@acay.com.au
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If my memory is correct, a company in the USA was the original developer/patenter of hard metal, cylinder bore surface treatments (chrome, etc.) during world war 2. I think this company was US CHROME.
This company also was the originator of what is currently described as "Nikasil". However, "Nikasil" may be a trade name registerd by the German company, Mahle. Mahle has been producing Nikasil cylinders since the seventies. And their quality is a world class leader.
I have been using "Nikasil" or clone cylinder coatings since the early '70's. In my opinion there is nothing else that comes close to wear, sealing, ring life, than Nikasil or other, similar nickel-silicon-carbide cylinder wall coatings.
I know this does not answer the root questions, but I wanted to get my experience/opinion out.
also does both SBC and Ford engines for the Aussie V8 Super Car engines.
At least a year or so ago, they expected to have the capacity to do V8's in a few months.
It was very pricey though, like about US$ 2000.00 I think for a cast iron V8
Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
I'm afraid I don't see anything at Electrosil's website regarding information the thread-starter is/was interested in- thermal conductivity, coefficient of thermal expansion, etc. of (generic?)Nikasil coatings/linings. Personally, I find what information is listed at that particular company's website to be catchphrase and cliche-ridden with little of real technical value. For instance, there's lots of talk about things such as "electroplated metal matrix", "hydrodynamic lubrication conditions", "oleophyllic structure of the coating and the unique Electrolube additive", "inbuilt lubricating barrier", etc. with nothing provided as far as substantiated evidence of data supporting these five-dollar-word descriptions and claims.
Cylinder sealing is a black art, even today, and I believe an engineer might be wise to be wary of accepting as gospel whatever latest fad happens to be in fashion, especially when it comes to "exotic" "race" engine treatments. After all, can anyone provide any kind of real proof that the hardest rings coupled with a Nykasil bore coating provide(as Electrosil claims) better sealing than a properly honed less-exotic bore liner with more conventional(or softer) rings? In what applications(after all, the original poster never stated that...)?
Please forgive me if I seem cynical but I must admit I was a bit disappointed with the website Pat, who's otherwise 100% on his game and spot on, provided. I'm just not buying the hype from that particular company, I suppose.
Let's discuss more? This is a very interesting topic.
I was not all that impressed with the site either, but it was vastly superior to the second best site I found, which was an advert for a motorcycle that used Nikasil coated bores as standard, and a bunch of sites about BMW and problems with there engines with Nikasil and sulfur in fuels.
I do know that a lot of very respected race engine builders use their service, despite the lack of hard data.
I would be very pleased to see better data if anyone finds it.
Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
My company has been in the race engine business for over thirty years. Without divulging any proprietary information I will say that we have been coating all of our cylinders for the last twenty years. Prior to that we purchased Nikasil cylinders from an OEM company back to the seventies.
We do not spend money on "black magic". We have to get race winning results.
The link below is one of the sources for coatings. There is considerable information available at the site. For more detailed information contact US Chrome, Millenium Technologies or Perfect Bore and talk to an engineer.
Also, one does not have to run a harder piston ring with these coatings. However, some ring materials may not be compatable with these coatings.
One good reason to utilize one of these coatings is the fact that a very fine Ra surface can be utilized. Simply stated, this reduces ring to cylinder liner friction tremendously. Also, piston scuffing is almost a thing of the past.