Carbon friction surfaces questions

[mattmartindrift]

I don’t plan on making any of these any time soon, however, while at the shop where my race car resides, they had a carbon fiber, twin-plate clutch. Now, I’ve seen these before, but I never really thought about it.

this clutch is what we had laying around:

I imagine these are all pressed pieces using some sort of mechanical/hydraulic press. But, then I thought about a binding agent, I know people talk about high-temp epoxies and such, but even those are only good to about 4-500*F.

Clutches get hot enough to create “hot spots” on their counterpart metal friction surfaces. Steel like that won’t usually mark (hot spot) unless it reaches the 1200*F range.

I’m curious about carbon brake systems as well, can anyone shed some light on this?

[riff42]

Something about Carbon-Carbon matrix. I think they some how compress carbon fibers with some sort of carbon binder.
Check out Composite World’s Sourcebook for some people that do taht stuff. I think they do it for high-temp curciables and racing/airplane brakes.

[KnottyBuoyz]

Many years ago when I was racing F2000 & Formula Atlantics our team participated in a number of factory product development programs on ceramic brakes and clutches. They’re not so much carbon fiber as they’re a carbon ceramic. The brakes would go past 2000 degs under hard use, I don’t know about the clutches but the way I used them they had to be under a lot of heat stress. Products like that take years and many millions in product development and testing before they ever reach the racing, let alone the street market.

[TET]

Many years ago when I was racing F2000 & Formula Atlantics our team participated in a number of factory product development programs on ceramic brakes and clutches. They’re not so much carbon fiber as they’re a carbon ceramic. The brakes would go past 2000 degs under hard use, I don’t know about the clutches but the way I used them they had to be under a lot of heat stress. Products like that take years and many millions in product development and testing before they ever reach the racing, let alone the street market.

You are talking about something different. These are not ceramic clutches.

I’m running a 5.5" twin disc carbon clutch in my track car. It’s just awesome for holding power, and engine response.
The carbon plates are NOT laminated like regular composites products. I’ve worked with a company that makes carbon brake discs for race cars and got to see the process. A basic explanation:
They lay up many plies of carbon fabric, special for this application, into metal tooling. It’s then clamped and put under pressure. This goes into an oven at VERY high temperature, for several weeks if I recall correctly. The layers get fused together, creating a solid block of carbon with basically a carbon matrix. This then gets machined to final size.

[KnottyBuoyz]

You are talking about something different. These are not ceramic clutches.

I’m running a 5.5" twin disc carbon clutch in my track car. It’s just awesome for holding power, and engine response.
The carbon plates are NOT laminated like regular composites products. I’ve worked with a company that makes carbon brake discs for race cars and got to see the process. A basic explanation:
They lay up many plies of carbon fabric, special for this application, into metal tooling. It’s then clamped and put under pressure. This goes into an oven at VERY high temperature, for several weeks if I recall correctly. The layers get fused together, creating a solid block of carbon with basically a carbon matrix. This then gets machined to final size.

I can only imagine what futuristic materials they use today. Way back then anything other than steel disk brakes and asbestos clutch plates was virtually unknown. Think the last time I drove a road course was 84. Made the switch to 1/4 mile pro street after that. I did drive a couple of Can-Am door slammers in the early 90’s that had many innovative components in composite materials. I drove a factory experimental Mustang GT back around 95 that had magnetic brakes on the rear axels. Now that was a wild ride!!! Don’t think they ever perfected that system although it’s used on larger machinery.

[mattmartindrift]

I just did a lot (3 hours bored at work) of research. To the best of my knowledge – which is limited – they use silicon carbide as the binding agent.

I believe this process involves some sort of silica/ceramic agent pressed in with the carbon fibers under high heat, pressure and with a constant inert gas flow through the product.

[TET]

I just did a lot (3 hours bored at work) of research. To the best of my knowledge – which is limited – they use silicon carbide as the binding agent.

I believe this process involves some sort of silica/ceramic agent pressed in with the carbon fibers under high heat, pressure and with a constant inert gas flow through the product.

I think you are looking at something different. Silicon carbide is used in clutches like the Carrera GT uses, and Porsche and Ferrari optional brakes which are made differently for each company. They are all carbon/ceramic.
The clutch I use is carbon/carbon, which is the same as brakes and clutches in F1 and LMP’s, and airplanes.

[riff42]

I think you are looking at something different. Silicon carbide is used in clutches like the Carrera GT uses, and Porsche and Ferrari optional brakes which are made differently for each company. They are all carbon/ceramic.
The clutch I use is carbon/carbon, which is the same as brakes and clutches in F1 and LMP’s, and airplanes.

yeah, carbon/carbon is different than carbon/ceramic. I think the high-temp, pressure, etc is the same though. I can’t see how else they can get full on carbon. Might be in the same line as monolithic carbon tooling?