Our institute in Stuttgart has a hot-air autoclave facility for producing complex, near-net-shape CFRP preforms (carbon fibre-reinforced plastic). The C-containing preforms are converted into ceramic matrix composites (CMC) in subsequent process steps.

Technical data Autoclave


Inner diamter

1200 mm

Cylindrical length

2750 mm

Operating temperature

350°C; zukünftig auch 400°C (max. 4K/min)

Operating medium

Heißluft; zukünftig auch Stickstoff

Operating pressure

20 bar

Vacuum under film bag

Pabs = 0,1 bar


Mainly, prepreg technology is used. The high pressure inside is used to compress the individual laminate layers with the help of a vacuum film bag in which the preform is located. A defined pressure, vacuum and temperature profile is applied to cure the fibre composite.


Daniel Cepli

German Aerospace Center (DLR)
Institute of Structures and Design
Pfaffenwaldring 38-40, 70569 Stuttgart