Title: Process Optimization for In-Situ Consolidation of Thermoplastic Structures with Fiber Steering Using Various Heating Methods and Tooling Concepts

Authors: Waruna Seneviratne, John Tomblin, Isaac Schmitz

DOI: 10.33599/nasampe/s.21.0507

Abstract: Reinforced thermoplastics (RTP) are now being considered for key aircraft structural applications and integration into automated manufacturing because of their impact, chemical, and flame resistance as well as resistance to aggressive environments. One of the challenges with the use of RTP for structural applications is they are extremely sensitive to processing variables. Due to numerous key processing parameters that contribute to final material characteristics, certification of RTP structures is challenging. Recent advances in laser and pulsed light solutions (Humm3) heating technologies and automated manufacturing technologies have enabled the use of thermoplastics in automated fiber placement (AFP) processes. Further process optimization via in-situ consolidation eliminates the need for secondary processing such as vacuum bagging and autoclave/oven curing, which significantly reduce the manufacturing cost and increase the production rates. In-situ consolidation coupled with automation provides tremendous advantages for improving the production rates, consistency, and part quality. In-situ consolidated panels were subjected detailed nondestructive inspection, thermal, physical, and mechanical characterization. Results were then compared against baseline press consolidated panels. Research was further expanded to investigate the impact of heated tooling on the part quality. Distinct trends in key physical and mechanical properties were shown to be coupled closely with nip point and heated tool temperatures. Crystallinity development was shown to possibly require unique processing such as preheating or possible tool design differences that are not utilized in standard AFP systems. Furthermore, inspection on a curved laminate showed in-situ consolidation is capable of achieving intimate contact between plies and good consolidation on even highly contoured parts.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000507

Pages: 12

Price: FREE