Contoured tape laying and fiber placement heads for automated fiber placement of large composite aerospace structures

摘要

Economic analyses comparing autoclave and candidate out-of-autoclave processes showed the promise of working thermoplastic in situ fiber placement and the more embryonic layer-by-layer E-Beam fiber placement process to fabricate large complex geometry composite primary structure out of the autoclave. Both processes feature a high normal force to compact the microstructure as an integral step in consolidating or curing the laminate, and show promise in fabricating parts. However, airframe and spaceframe complex geometry parts include both singly and doubly curved skins that require conformance on a large scale, and padups, pandowns, ply details, and joggles that appear on curved and even flat laminates. Thus, it was concluded that both processes would be ineffective without incorporating a proven conformable compaction system in a contoured deposition head to provide for an adequate normal consolidation force while placing the complex geometric shapes. Sponsored by a NASA Phase II SBIR program now underway, this project's goal is to develop and prove out a number of innovative conformable compactors for assembly into deposition heads. This paper describes the need for conformable compactors for ATP deposition heads, reviews the specification for the compactors, shows the overall process concept and equipment, then describes the compaction module hardware and shows demonstration parts made to date using the contoured head.