Session: 03-12-01: Structural Bonding and Surface Modifications

Paper Number: 190160

190160 - Fracture Analysis of Intra- and Inter-Bead Bonding in Large-Area Additive Manufactured Polymer Composites 

Large-Area Additive Manufacturing (LAAM) is increasingly adopted for producing meter-scale polymer composite structures in aerospace tooling and secondary structures. However, manufacturing-induced defects, such as intrabead microvoids and weak interbead bonding, significantly degrade fracture performance and complicate the material qualification step.  

This study presents a newly developed double cantilever beam with doublers (DCB-D) fracture test tailored for large-area additively manufactured materials, together with a rigorous data reduction framework that enables accurate extraction of intrinsic intrabead and interbead fracture properties. To this end, rigid doublers are adhesively bonded to the DCB specimens to suppress compressive crushing and crack-tip instability commonly observed in large-bead architectures, allowing stable crack propagation to be measured in single-bead, double-bead, and multi-bead configurations. However, the presence of doublers alters the local compliance and stress field, rendering conventional data reduction methods inappropriate. To address this, a new data reduction methodology is developed to remove the mechanical influence of the doublers, yielding ‘pure’ energy release rate values representative of printed material architecture. The approach is applied to LAAM-based neat acrylonitrile butadiene styrene (ABS) and short carbon fiber-reinforced ABS (CF/ABS).  

Our results show enhanced intrabead damage tolerance in CF/ABS due to fiber pull-out and bridging, while interbead fracture resistance is reduced relative to ABS, attributed to voids and reduced polymer interdiffusion at bead interfaces. X-ray computed tomography confirms the role of interbead porosity in accelerating crack initiation and growth. The proposed DCB-D test and accompanying data reduction methodology provide a robust, scalable framework for quantifying fracture properties of large-area additively manufactured materials, enabling more reliable damage-tolerant design and accelerated qualification of aerospace structures. 

References: 

[1] Arief Yudhanto, Neshat Sayah, Douglas E. Smith, Intrabead and interbead fracture analysis of large area additive manufactured polymer and polymer composites, Composites Science and Technology, Volume 266, 2025, 111173 

[2] Arief Yudhanto, Neshat Sayah, Douglas E. Smith. Interlayer Fracture of Large Area Additive Manufactured Short Fiber Composites, 35th Annual International Solid Freeform Fabrication (SFF) Symposium, An Additive Manufacturing Conference 2024, pp. 113-124 

Presenting Author: Arief Yudhanto Missouri S&T

Presenting Author Biography: Dr. Arief Yudhanto is an Assistant Professor of Aerospace Engineering in the Mechanical and Aerospace Engineering Department at Missouri University of Science and Technology (Missouri S&T), Rolla, Missouri, USA. He is also the Director of Composites Aerostructures Laboratory at Missouri S&T. His laboratory focuses on developing experimental and computational methods to reveal fundamental mechanics and damage mechanisms of composite structures and other engineering materials used in modern vehicles. Prior to his current appointment, he used to work at Baylor University in Waco TX, KAUST in Saudi Arabia, TMU Japan, Hitachi GST/IBM Singapore, A*STAR DSI Singapore.

He has been working specifically in the computational and experimental aspects of advanced composite materials for over 20 years. He received the SABIC Recognition Award for university-industry collaboration. His research interests include (i) Adhesively Bonded Composite Joints and Interface Mechanics, (ii) Damage and Fracture Mechanics/Mechanisms, (iii) Digital Image Correlation and NDE (X-ray Micro-Computed Tomography), (iv) Fatigue of Composite Materials and Structures, (v) Finite Element Modeling of Intralaminar/Interlaminar Damage, (vi) Homogenization Methods (Asymptotic Expansion), (vi) Impact Mechanics and Crashworthiness, (vii) Large-Format Additive Manufacturing, (viii) Manufacturing of Thermoset and Thermoplastic Composites, (ix) Stitched and 3D Woven Composites.

He earned his Ph.D. in Aerospace Engineering (Experimental and Computational Mechanics) from Tokyo Metropolitan University, Japan, after conducting research at Advanced Composites Technology Center of JAXA (Japan Aerospace Exploration Agency). He also holds a Master of Engineering degree in Mechanical Engineering (Computational Mechanics) from the National University of Singapore (NUS) and a Bachelor of Engineering degree in Aeronautics & Astronautics (Computational Mechanics) from Bandung Institute of Technology (ITB), Indonesia.