Title: Process Design and Optimization for an Aerospace Demonstrator Using Modern Material and Tooling Systems

Authors: Tanner J. Empey, Andrew R. George, Jason W. Scharf, Tim Carlson, John Manning, Jason Burgess, Devin Young

DOI: 10.33599/nasampe/s.22.0868

Abstract: The high cycle times and low production rates in modern aerospace manufacturing are at least somewhat attributable to the cost and time required to design and optimize a new process, and/or to qualify new material systems. The objective of this study was to develop and demonstrate a methodology for the design and optimization of a liquid composite molding (LCM) manufacturing practice, to produce a demonstrator aerospace part. Modern material systems were chosen for the demonstration, namely a veil-bindered carbon biaxial non-crimp fabric and an oven cure epoxy. Material characterization testing was done to measure the compressibility and permeability of the reinforcement, as well as the isothermal viscosity development of the resin. This data was used to simulate the manufacture of a demonstrator aerospace part by both vacuum infusion and RTM processing. The debulking behavior was characterized for heat-treated preforms from this reinforcement, to determine the maximum fiber content capabilities under a vacuum bag, and how that increases with the number of debulking cycles. Flat panels were made by both VI and RTM with the candidate materials. These cured laminates were tested for short beam shear strength, and resulted in similar numbers between the two processing types. The challenges to scaling from vacuum infusion to an RTM process are discussed in context of these experiments and simulations. This includes buckling risks in rigid tooling due to the preforming’s effect on in-plane reinforcement stiffness, and the high pressure, multiple inlet designs, or RTM-variants that would allow complete infusion of the highly dense preforms. In addition, the viability of 3D printed tooling for LCM processing was investigated, by evaluating both sanding and flame treatment methods to change the texturized printed tooling surface into a sealable surface for part release.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000868

Pages: 19

Price: $38.00