Carbon Block?

[Carbon]

A question to the engineers on this forum. Is it possible to develop a carbon fibre engine block? I know there are iron, aluminum and magnesium blocks used in production cars and race engines, and carbon is used in gearbox housing, what are the limiting factors for using the same material in a block? Has this been experimented with at all?

[Scuderia_Russ]

Don't know enough about carbon to answer but I know that a largely plastic one has been constructed before.

[Monstrobolaxa]

hummm.....no!

Using carbon fibre reinforced plastics as in the monocoque...isn't viable cause the epoxy resin in the combustion chamber would overheat and "burn".

Using a carbon base like the brake discs and pads wouldn't work either...once again inside the combustion chamber the friction between the piston and the wall...and the heat would wear out the wall and would also oxidize the carbon....

[manchild]

hummm.....no!

Using carbon fibre reinforced plastics as in the monocoque...isn't viable cause the epoxy resin in the combustion chamber would overheat and "burn".

Using a carbon base like the brake discs and pads wouldn't work either...once again inside the combustion chamber the friction between the piston and the wall...and the heat would wear out the wall and would also oxidize the carbon....

Even with wet liners made of metal?

[Monstrobolaxa]

hummm.....no!

Using carbon fibre reinforced plastics as in the monocoque...isn't viable cause the epoxy resin in the combustion chamber would overheat and "burn".

Using a carbon base like the brake discs and pads wouldn't work either...once again inside the combustion chamber the friction between the piston and the wall...and the heat would wear out the wall and would also oxidize the carbon....

Even with wet liners made of metal?

In my opinion it wouldn't work anyway....metal has a very high heat conduction coeficient (don't know the exact name in english) so alot of the heat generated in the combustion chamber would end up reaching the carbon! Probably with metal liners it would reduce the oxidation...

[Guest]

hummm.....no!

Using carbon fibre reinforced plastics as in the monocoque...isn't viable cause the epoxy resin in the combustion chamber would overheat and "burn".

Using a carbon base like the brake discs and pads wouldn't work either...once again inside the combustion chamber the friction between the piston and the wall...and the heat would wear out the wall and would also oxidize the carbon....

This is correct. Pure carbon Fibre cant be used in this area. However, what can be done is creating a carbon based alloy. We have sucessfully utilised this material in pistons for our model car engines with not only decreased wear rate but also increased power levels. Granted these are only 2.11cc engine but they run on Nitromethanol at over 50k rpm. Compared with convential Aluminium Pistons which last approx 3-4hrs at 43k rpm we are getting over 10hrs running time before any mild wear starts to show. if Utilised into F1 I reckon while being slightly more expensive short term it would give better performance and lower costs long term.

[Carbon]

Thanks for all the insight and feedback, much appreciated.

[riff_raff]

A carbon fiber engine block would not be a practical proposition because carbon fiber does not have the necessary physical properties to make a good engine block. As for "composite" engine materials, take a look at BMW's 5-series engine blocks- they are a composite of aluminum and magnesium.

Other fiber reinforced materials, such as MMC's like SiC reinforced aluminum, have found their way into high-performance engine components such as cylinder liners and pistons. Honda even has MMC materials in some of their production engines.

Of course, all of these materials are outlawed for F1.

[P.Williams]

Carbon fiber is rarely used as a single. It's always used with epoxy as a matrix to form a composite.

The carbon fiber - epoxy resin composite cannot be used on engine block, because carbon fiber is a directional material, that means when it's under impact, the composite can support huge strength when the force is parallel to the fiber direction, but support low when the force is perpendicular to the fiber direction. Therefore it's hard to design as an engine block and complicated in manufacture.

Aluminium magnesium alloy (metal is non-directional) is suitable for making engine block. Different material can block the dislocations moving of the material to increase the strength.

The carbon is used in gearbox to increase the wear resistance. The physical property for carbon and carbon fiber are different. The best design for using carbon fiber-epoxy composite is chassis or car shell of F1.

I dont know this ans can help you or not....

[dumrick]

what can be done is creating a carbon based alloy. We have sucessfully utilised this material in pistons for our model car engines with not only decreased wear rate but also increased power levels.

Max Mosley's policies are slowly making F1 less technologically advanced than model car racing...

Sorry for being OT...

[riff_raff]

I have seen people try to make pistons of carbon-carbon. While it is physically possible, it usually does not work out well simply because carbon-carbon does not conduct heat adequately. And any heat that is not tranferred away thru the piston crown usually ends up increasing the temperature at the ring-to-liner interface (it's got to go somewhere). Once the bore surface of the cylinder liner reaches about 350degF, the lubricating oil film begins to flash off and the piston rings will rapidly gall and fail. Piston rings work and last because there is always a boundary lubrication condition present at the ring to liner interface. Thus the piston and cylinder liner must be made of a material that will conduct heat sufficiently to maintain surface temperatures below the flash point of the engine lubricant.

[Mikey_s]

Riff-Raff,

if the piston was made of carbon why would it not burn?? there should be enough oxygen around....

[Cyco]

riff_raff: Have a look at Performance Friction's new carbon-carbon brake rotors. They (it would appear from my reading) are having the whole part woven as a unit which gives them fibres running transversly (in your case ligditudinaly) and that allows th temp to flow more easily and lower surface temps. Doing this could help solve your problems. If a may ask, what weiight savaings have you managed to achieve with the CC pistons so far?

As to a CF block: With liners I would consider it possible, an epoxy matrix is unlikly to work, but a BMI matrix will cope with the heat levels generated easily.

[James_graham]

You will also need to look at the properties of the resin system. Epoxy would not be able to see thetemperatures at the rear of a racing car (around the engine/exhaust) which is why it is not used. Many teams use a phenolic resin as a matrix for the composite which can see the temperature. Couple that with a metal coating and it may well be possible.

[The FOZ]

Plastic-based resins would not survive in this sort of application.

But that isn't to say metal matrix composites, or phenolic or ceramic matrix carbon can't work.

Also: Brakes are already carbon-carbon. They see far more heat than an engine block.

It could be done, in theory. It would just take decades to develop. Much like the decades we have into aluminium alloy blocks right now. I bet the first aluminium blocks were garbage, too. Conventional knowledge was that aluminum had too great a coefficient of thermal expansion. My point is, we'd never know how far it can go until we've gotten there.