Carbon Fiber Reinforced Polymer

[jdsewell]

Forgive my ignorance.

1. Can CFRP's be injection molded? If so are there any special considerations for the process or can an injection molding machine capable of fiber reinforced plastics (such as ABS) do the job?

2. A few months back I read an article on the web discussing the use of pitch precursor carbon fibers instead of the more traditional PAN for CFRP's for applications requiring high thermal conductivity (the article claimed conductivity higher than copper). The example given was a servor motor with a case integrated heatsink. I'm having difficulting finding a manufacturer for pitch CFRP. Is this something new or just something with no market and therefore no manufacturers?

Thank you for your attention.

 

[stimpee]

Conoco had created a very low cost pitch carbon fiber product in the last few years for just that type of purpose. It had excellent thermal conductivity and stiffness, but was in a form that made it difficult to use for structural applications.

They had gone as far as to put a plant together somewhere down south to produce the material, however I think they recently last 6 months or so) canned it with the Philips merger, etc.

You may want to poke around a bit and see what you can find though...

Also, short fiber composites can be injection molded. I don't know too much about it though, and carbon fiber would probably create havoc with machines and tooling due to its abrasive nature...

 

[Compositepro]

The high thermal conductivity fibers are made by Cytec Carbon Fibers (formerly BP/AMOCO fibers). They are several times more thermally conductive than copper, but only in the fiber direction, and they are very expensive (over $1000 per pound for continuous fiber). Chopped fiber is used in molding compounds but chopping greatly reduces thermal conuctivity.

Nothing beats heat pipes for conducting heat over significant distances. Heat pipes can have thermal conductivity equivalent to 50,000 times that of copper.