Accudyne proposes a SBIR program, endorsed by Sikorsky, Cytec Engineered Materials, and NASA-LaRC, to develop a cost-effective thermoplastic automated tow placement (ATP) process and demonstrate it by fabricating and testing a complex contoured skin (Phase 1) and a CH-53K rotorcraft lower cabin or ramp skin (Phase 2). The process employs in situ consolidation, avoiding the autoclave. The targeted part properties are those measured from autoclave-consolidated laminates. The selected Cytec APC-2 material system features inherent toughness, matching rotorcraft application requirements. For Phase 1, Accudyne will employ their already operating thermoplastic heated head that features full conformable compactors, individual tow-cut-and-add, and creates excellent microstructure. This plan will allow the rapid identification of the challenges to fabricating the complex contoured parts. Following Phase 2, Accudyne will offer an automated fiber placement machine and heated head for sale to the industry that is capable of fabricating the desired parts without using the autoclave.
Benefit: The successful demonstration of out-of-autoclave thermoplastic ATP processing yielding full mechanical properties would yield noteworthy benefits for NAVAIR, NAVAIR OEMs, suppliers, and the US aerospace industry generally. NAVAIR can stimulate the adoption of the cost-effective in situ ATP process at OEMs and benefit from longer life rotorcraft skins with higher toughness. This could benefit the CH-53K and other rotorcraft. Other OEMs of interest to NAVAIR, and the US aerospace industry generally, can adopt thermoplastic AFP/ATP to (i) eliminate the capital and operating cost of autoclaves and significantly lower the cost to fabricate large composite parts for Navy fighters, commercial transport aircraft, and spacecraft; (ii) adopt lower weight aerospace structure since larger parts can be fabricated out-of-the-autoclave (consolidating multiple small parts into large components eliminates the weight and cost of joining); (iii) benefit from mechanical properties in the composite equal or superior to those generated from laminates fabricated using todays autoclave process (for example APC-2 AS-4 IPSS of 154MPa already exceeds the 102MPa baseline from AS-4/8552); and (iv) benefit from additional thermoplastic resin characteristics, for example, high temperature performance, elevated toughness, superior solvent resistance, and environmental durability. Machine builders like Cincinnati Machine could develop and offer for sale a new class of thermoplastic fiber placement machines to US aerospace primes. Further, the technology could be extended from fiber placement to tape placement so a number of additional fuselage, wing skin, rocket motor, and tank applications could be considered. Material suppliers like Cytec Engineered Materials could develop and offer for sale a new class of placement-grade thermoplastic tow and tape material systems to US aerospace primes.
Keywords: Insitu Consolidation, Insitu Consolidation, Out of Autoclave Process, Tow Placement, thermoplastics, Conformable Compaction, AS-4/PEKK, Fiber Placement, Contoured Fiber Placement
