Title: Additive Manufacturing of Phenolic-Based Composites for Thermal Protection Systems

Authors: Alison I. Kennedy, Steven R. Nutt, Kyle Brubaker, Eric Kroon

DOI: 10.33599/nasampe/c.22.0167

Abstract: Thermal protection systems are vital to ensure that aerospace vehicles are not deteriorated by atmospheric heating. Typically, these systems consist of tiles applied by hand, which presents an expensive and time-consuming process. Using additive manufacturing allows for this process to be automated while preserving the intricate designs of the tiles. Various phenolic resin systems were analyzed to find a printable material that can undergo in-situ curing. Char yield values, mechanical properties, and cure kinetics were analyzed. A model was developed for gelation prediction in order to determine the time allotted for the material to be workable. Additionally, the activation energies of the cure reactions were calculated from rheometry data using the Arrhenius equation. The morphology was also studied through microscopy, which was further analyzed to determine the distribution of additives within the matrix. These include materials that increase the mechanical properties while reducing the density, which ensure that there is adequate protection while minimizing the amount of fuel needed to account for the weight of the thermal protection systems. The imaging showed an even distribution of these additives while also displaying minimal voids. Future work includes demonstration of printing capabilities that are scaled up to the dimensions needed for the practical application.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000167

Pages: 12

Price: $24.00