An article is made by co-curing a lay up on a composite bond jig of fiber-reinforced composite materials having a lower layer, at least one elongated hollow mandrel of a stiffened graphite fabric having its lower surface adhered to the upper surface of the lower layer, and an upper layer adhered to the...http://www.google.de/patents/US6458309?utm_source=gb-gplus-sharePatent US6458309 - Method for fabricating an advanced composite aerostructure article having an integral co-cured fly away hollow mandrel
