Very High TG Prepreg

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#1

Hey guys,

I have a bit of a problem, I need to build a straight tube (8000mm x 30mm) to replace an aluminium tube of the same dimentions.

Here is the problem, it is used inside the exhaust of a turbine and the ambient temp is 1400°C

The aluminium tube was cooled internally with water, and the CF would be too, and since it didn’t melt, I assume it never went over 660°C. The Al tube is too heavy, as it needs to be handled by someone(think of it as a very long broom stick)

I need a prepreg/resin system that can be produced OOAC and still survive.

I have found:

hexcel m65 BMI prepreg that has a 300°C Tg
P2si N18 (tg 360°C)

P2si 900HT can handle 454°C but needs to be autoclaved at 200psi.

Alternatively Starfire Polyramic Resins can do 1000°C+ but needs to be cured in an inert gas at 850°C

Is there anybody that has experience with any of these systems or others that have worked? Ease of processing is important, but in the end, the cost is not a big factor.

Any help would be appreciated.

#2

Hi, look here
http://www.high-temperature-composites.com/high-temperature-composites-and-fire-barriers-pyrosic-pyrokarb.htm

#3

Thanks, that seems to be the solution.

I can’t figure out if they sell their system or only manufacture parts.

#4

i believe they only manufacture parts. i was reading someones post in another thread that said they like to keep production in house.

the amount of money and the complex curing processes involved in Ceramic Matrix Composites (CMC) are wayyyyyyyyyyyyyyyy out of most peoples league. not saying u dont know what your doing, im just saying it seems very very complicated.

#5

I have tracked down a very high tg (320C) EPOXY (!) prepreg. Im getting it through a contact, so the manufacturer is unknown. It is a B-stage product with no tack whatsoever, so it must be pressed. Let me know if youre interested, Im getting a 10 metre sample with the possibility of buying 100-200 metres in the future.

#6

can i ask whats wrong with an inconel tube?

Please feel free to send me a message off board i have experince of ceramic exhausts and Inconel exhausts also pyromeral and other ceramic composite materials companies