Title: Additively Manufactured Thermoplastic π-joint for eVTOL

Authors: Umesh Marathe, Chinmay Mungale, Segun Isaac Talabi, Adwoa Owusu, Brittany Rodriguez, David Nuttall, Aniruddh Vashisth, John Geriguis, Nobi Kawamura, Dan Coughlin, Vipin Kumar

DOI:

Abstract: Bonded composite π-joints are critical to support wing geometries in aerospace/aircraft structures. Its lightweight and robust load-bearing capabilities/design guarantee high structural integrity and reliability. Current manufacturing techniques of π-joints are complex and laborious, and do not always offer high-quality joining. This study presents a high-rate manufacturing approach to fabricate π-joints using an integrated Additive Manufacturing and Compression Molding (AMCM) process. The joints were manufactured using unidirectional aerospace-grade LMPAEK/CF at 60% fiber loading for the stiffeners/skin and LM-PAEK/GF as the adhesive and characterized to evaluate their microstructure and strength. While the results indicate void formation at the joint caused by inadequate pressure, the peak tensile load of 600N recorded is akin to injection-autoclave molded π-joints, which validates the potential of this high-rate integrated approach to eliminate time-consuming and labour-intensive processes of making πjoints to reduce cost and produce high-quality joints.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 157

Pages: 16

Price: $32.00