Graphite Heat-Sinks are available from at least one place I know of - Mersen (
www.mersen.com). I actually had Cliff W. in my conference room three days ago - he's the Mersen "Graphite Techno-Geek".
From our discussions, It sounds like graphite is an awesome material with a ton of potential.. However, there are a few downsides that have yet to be solved.
1) The Graphite is pretty brittle and will shatter pretty easily.
2) The Graphite isn't resistant to chemicals or even to water in any quantity.
3) Graphite conducts heat in only two planes. In the third plane, it's a REALLY good insulator (amazing, isn't it). Makes it very good for 'fins' and very very very very very bad for the base of a heat sink.
4) The claims that it's more thermally conductive that copper are absolutely not true. It's roughly equal to copper, but it's slightly LIGHTER than Aluminum. That is the huge advantage of Graphite - it's Thermal Conductivity to weight ratio. Price wise, it's roughly equal to or slightly more expensive than copper (currently). That may change as it's usage becomes more prevalent.
Ben
