have seen it done to tops of pistons, faces of valves,
you could consider doing it to the face of head... but not piston skirt or sleeves below the top ring.
Was just reminded by another thread on ceramic coating on IC piping... What about on piston/cylinder sleeves?
I would assume it'd be an expensive and complicated process, but has it been done, or can it be done?
have seen it done to tops of pistons, faces of valves,
you could consider doing it to the face of head... but not piston skirt or sleeves below the top ring.
Why would you want to do this, even if it were possible?
Norbie!
www.norbie.net
Umm, yeah why...
Wouldn't it fuck the hone pattern and hence the oiling characteristics of the engine?...
You can HPC the piston skirts and crowns tho...
Cheers
Wilbo
Because a ceramic coating on both the Piston and Bore would reduce the friction to a very low level, a hone wouldn't be necessary in such a situation I would have thought.
Reducing friction, that's why engines have oil in them.
Norbie!
www.norbie.net
But using ceramic would reduce the friction still. Oil isn't perfect.
there is a company that do similar, i will try and find their address.
it is a thermal spray process, but they spray a combination of iron, iron oxide, (and maybe other stuff like nickel) onto aluminium bores....(saw it at a conference )
they had a nifty, center-aligned, continuous wire weeds, around which the arc? rotated...
these guys the PTWA process
http://www.flame-spray.com/home.htm
this is a cool pic they also showed they can coat the inside of conrods.. ie, say, titanium rods and give a thin coating of bronze, instead of using a bushing
there are issues with ceramic...
surface finish, plasma spray/thermal spray could be a bit rough, and wear rings out quickly
consistency.. having the same thickness coating all the way round.
adhesion.. as soon as you loose a little piece of it, the engine is fucked.
thermal expansion... not a good property of most ceramics.
HPC do a non-oil-sticking coating for piston sides.... i would think the rings might be better sliding on a metal surface (with the correct proportion of rough/smooth areas) than on a relatively rough ceramic surface...
with a better prepared bore (ie, round and straight), lower ring tension (or indeed, lower gas pressure behind the ring) is needed to keep a good seal....
here is a little reading
http://www.sciencedirect.com/science...d1f29214e1bd8d
i think now, manufacturers are trying to coat aluminium blocks with iron, or something that mimics cast iron, as it has excellent wear and friction. the iron with iron oxide coatings are better, as the iron oxide reduces friction and wear, and (when i asked ) does not reduce heat trasnfer from the rings to the cylinder block....
perhaps the main problem with ceramic bore coating.. is that all the piston heat cannot escape, unless you increase cooling from below.... rings get too hot (from combustion and friction) and bad things happen....
whatcha think?
"I'm a Teaspoon, not a mechanic"
"There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)
AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!
nah it cant be done. It would wear off in minutes!
The stuff is good but it aint that good
300+rwkw 4agte http://www.toymods.org.au/forums/for...wkw-4agte.html
oh, and for top of pistons, by all means ceramic coat!!! reducing heat loss from combustion chamber thru piston can only be a good thing, although changes to compression/boost etc, might be needed if there is more heat retained in the charge (which is better for power..no?)
HPC definitely can coat piston tops in ceramic, and sides in slippery stuff, under pistons with oil-non-stick, combustion chambers, valves and ports with ceramic.. and it is not really that expensive..
maybe $500-600 for a 4 cylinder engine?? i will definitely consider it for next build.. esp ports and valves... less heat = better
"I'm a Teaspoon, not a mechanic"
"There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)
AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!
I think Keronite can be used on bores .... ?
It's amazing stuff though, check ti out.
http://www.keronite.com
www.billzilla.org
Toymods founding member #3
and here is some more technical info on it
http://www.azom.com/details.asp?ArticleID=1438
thats really really interesting!!
plasma assisted anodising, but allowing codepsition to form more complex oxides, from the solution!!
you instead of just alumina, you can get a mixed oxide, and probably without the pores usualyl associated with normal anodising!!
being 3-400 microns thick, you would need to bore prior to coating with the thickness in mind.
the external layer looks a little... flaky.. and might be be damaged/cause damage if it spalls...
still have the issue of decreased ring cooling tho?
Last edited by oldcorollas; 19-01-2007 at 06:12 PM.
"I'm a Teaspoon, not a mechanic"
"There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)
AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!
Okay, so not good for bores sorry.
But I know it's great stuff in lots of other applications.
</hijack>
www.billzilla.org
Toymods founding member #3
indeed it does look good
thanks for the info!
(check out the PTAW.. i reckon that will be the way of the near future, and is already being used in some high end engines.. i think audi exxy diesels?)
"I'm a Teaspoon, not a mechanic"
"There is hardly anything in the world that a man can not make a little worse and sell a little cheaper" - John Ruskin (1819 - 1900)
AU$TRALIA... come and stay and PAY and PAY!!! The moral high horse of the world!
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