2026 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2026): Materials: Composites
Program Organizers: David Leigh, University of Texas at Austin
Tuesday 8:00 AM
August 4, 2026
Room: Guadalupe
Location: AT&T Center
8:00 AM
Acoustic Field-Assisted Direct Ink Writing of High-Performance Nanocomposites: Owen Smith1; Yuqing Feng1; Wesley Owens1; Ziao Guo1; Yingbin Hu1; 1Mississippi State University
Owing to their unique properties brought by nanosized reinforcements, nanocomposites offer a broad range of benefits, thus attracting extensive attention and being widely applied to automotive, biomedical, aerospace, and other high-tech industries. As a flexible additive manufacturing (AM) method, direct ink writing (DIW) shows great promise for processing a wide variety of nanocomposites at low cost. Despite these benefits, problems still exist in DIW of nanocomposites, such as entrapped air bubbles and agglomerations of nanosized reinforcements. Facing these challenges, we have integrated acoustic field with DIW to provide real-time ultrasonic vibration during the printing process. In this investigation, graphene is selected to reinforce polydimethylsiloxane due to graphene’s high stiffness and strength, low density, and efficiency in property enhancement with a little addition. Experimental results evidenced that the integration of acoustic field is beneficial for reducing air bubbles, homogenizing graphene distribution, and enhancing mechanical performance.
8:20 AM
Evaluation of Shear Flow-Induced Orientation Eeffects on Magnetic Platelet Particles in Extrusion-Deposition Additive Manufacturing Polymer Processing: Douglas Smith1; Anil Mandal2; Md Anisul Islam2; Leo Rodriguez2; Wilhelmus Geerts2; Jitendra Tate2; 1Baylor University; 2Texas State University
Custom magnets have been produced with polymer composite extrusion/deposition additive manufacturing using Strontiumferrite/PA12 filaments where magnetic anisotropy appears to be significantly affected by the interaction of particles with the flow field. This paper considers the effect of shear flow during processing on the orientation of suspended magnetic particles. Non-spherical SFO particles are modeled as oblate ellipsoids in a dilute suspension where orientation is evaluated using both Jeffery’s equation for single particles and orientation tensors for groups of particles. Monte Carlo simulations are performed to model orientation distributions in the Jeffery’s simulations, and the Exact Closure facilitates orientation tensor evolution calculations. Predicted particle orientations are compared with measured magnetic squareness for freely extruded strands and printed bead samples. Preliminary results indicate that flow-induced particle orientation may explain the measured orientation of the easy magnetic anisotropy axes in the extrusion/deposition samples.
8:40 AM
Extrusion-Based Additive Manufacturing of Strontium Ferrite–Polyamide 12 Bonded Magnets via Controlled Particle Size Distribution: SHOURAV GHOSH1; Pratik Karkhanis1; Jitendra Tate1; 1Texas State University
Extrusion-based additive manufacturing offers unique opportunities to fabricate net-shaped polymer-bonded magnets with tailored geometries. However, magnetic output remains constrained by inefficient particle packing and limited magnetic volume fraction. In this study, a strontium ferrite–polyamide 12 (PA12) composite was developed using a broadened particle size distribution to improve packing density and enhance magnetic response. Anisotropic strontium ferrite powder (~1 μm) was subjected to wet ball-milling to generate a finer fraction, and the two powders were blended in controlled ratios to promote efficient void filling within the PA12 matrix. The composite was compounded into filament via single-screw extrusion and fabricated using Fused Filament Fabrication (FFF). Mechanical properties were evaluated through tensile and flexural testing, magnetic properties via VSM, and microstructural analysis were performed using Axia Chemi SEM. Results demonstrate that controlled particle size distribution broadening is an effective strategy for enhancing magnetic performance while preserving processability in extrusion based bonded magnets.
9:00 AM
Flame-Retardant Bonded Magnetic Composites for Extrusion-Based 3D Printing: Pratik U. Karkhanis1; Shourav Ghosh1; Mir Imran Bin Samad1; Roshan Poudel1; Stirling Moss1; Joben Rios1; Wyatt Lange 1; Jitendra Tate1; 1Texas State University - San Marcos
Polymer-bonded magnets are widely used for sensing, actuation, and electromagnetic interference (EMI) shielding due to their design flexibility; however, their use is limited by the inherent flammability of conventional polyamide–ferrite systems. With the growing adoption of fused filament fabrication (FFF), there is a critical need for fire-safe, magnetically functional materials compatible with additive manufacturing. This study presents a halogen-free, flame-retardant, bonded-magnetic composite based on a polyamide 6 (PA6) matrix incorporating strontium ferrite, melamine polyphosphate (MPP), and glass fibers. The composite is fabricated via single- and twin-screw extrusion to achieve uniform dispersion, robust interfacial interactions, and stable processing for FFF. A synergistic phosphorus–nitrogen flame-retardant mechanism enhances char formation and thermal stability. Flame retardancy is evaluated using the Limiting Oxygen Index (LOI), along with TGA, DSC, SEM, and VSM characterization. The composite retains anisotropic magnetic behavior after printing, enabling functional performance in fire-critical additive manufacturing applications.
9:20 AM
Fused Deposition Modeling of Polyethylene/Boron Carbide Composites: Arturo Hernandez-Barreto1; Carolyn Long2; Jan Bandong2; Jason Benkoski2; John Bernardin2; Sheldon Landsberger1; Desiderio Kovar1; 1The University of Texas at Austin; 2Los Alamos National Laboratory
Polyethylene and boron carbide are widely favored for neutron shielding due to their roles as an effective moderator and absorber, respectively. Additive manufacturing of polyethylene/boron carbide composites offers the potential to create neutron shielding components with tailored geometries and compositions. Fused deposition modeling is a widely accessible additive manufacturing method, making it an attractive fabrication route. In this work, polyethylene filaments with a range of boron carbide loadings were produced, and selected compositions were printed into tensile coupons. The challenges and associated troubleshooting methods that arose during filament fabrication and printing of these composites are outlined.
9:40 AM Break
10:00 AM
Using Near-Net Shape Structures Printed by Fused Filament Fabrication to Characterize Tensile Property Anisotropy in Composite Polymers: Ian Rybak1; Miguel Cubillas1; Joseph Mckee1; Joshua Green1; 1University of Texas at El Paso
Extrusion in fused filament fabrication (FFF) processes introduce anisotropy which impacts the ability to measure, model, and predict performance in printed composite parts. As composites are increasingly adopted in FFF and consideration for anisotropic properties are integrated into print planning operations, effective characterization techniques are needed for determining anisotropic properties in FFF-printed materials. To isolate and evaluate polymer composite tensile properties with loads relative to print X-Y axes and build direction without extrusion gaps convoluting the results, high density structures with extrusions parallel to the X axis, much like near-net-shape printing, were printed and machined into individual tensile specimens such that load is applied to a single axis orientation. Polylactic acid composites were printed, characterized, and tested using these methods and were compared to conventionally printed net-shape tensile specimens. This work overcomes persistent challenges in characterizing tensile properties and provides a reference for the mechanical effects resulting from extrusion gaps.
10:20 AM
Thermal, Electrical, and Shape Memory Performance of Multifunctional TPU/PCL–SWCNT Composites for Additive Manufacturing: Bahaa Shaqour1; Vincent Berthé1; Joamin GONZALEZ-GUTIERREZ1; 1Luxembourg Institute of Science and Technology
This study reports the development of multifunctional composites based on thermoplastic polyurethane (TPU) and polycaprolactone (PCL) blends loaded with single-walled carbon nanotubes (SWCNT) for electroactive and shape memory applications. TPU was blended with varying loadings of a PCL-SWCNT masterbatch. The prepared formulations were systematically characterized to investigate their thermal, physicochemical, electrical, and shape memory properties. Thermal analysis revealed that the presence of PCL introduces distinct thermal transition, enabling tunable switching temperatures, while SWCNT incorporation enhances thermal stability. Physicochemical evaluations indicated improved filler network formation and dispersion, influencing processability. Electrical conductivity measurements demonstrated a clear percolation threshold, enabling efficient Joule heating at various SWCNT contents. This electrically conductive network was exploited to trigger and control shape memory recovery, showing rapid and programmable actuation. The results highlight the synergistic role of TPU elasticity, PCL crystallinity, and SWCNT conductivity in designing smart, electrically responsive materials for 3D printing applications.
10:40 AM
Development and Characterization of Hybrid Nanocomposite Photocurable Resin for Vat Photopolymerization: Rahul Sheley1; Prakash Rai1; Brady Simons1; Pete Caranikas1; Luke Liesmann1; Sandy Hernandez Herrera1; Jitendra Tate1; 1Texas State University
Vat photopolymerization fabricates high-resolution polymer components for functional engineering applications, but stereolithography-printed parts often require nickel coatings to improve mechanical, electrical, and thermal performance. A key limitation is coating failure at elevated temperatures caused by coefficient-of-thermal-expansion mismatch between the polymer and metallic coating. This study develops thermally stable photocurable nanocomposite resins for DLP stereolithography using hybrid nanofiller reinforcement.The resin systems were formulated with bisphenol A epoxy diacrylate as the base oligomer and trimethylolpropane triacrylate as the reactive diluent. Photopolymerization was initiated using TPO and BAPO photoinitiators. Multi-walled carbon nanotubes, hexagonal boron nitride, and nanosilica were incorporated as hybrid reinforcements. The base resin and hexagonal boron nitride content were held constant, while multi-walled carbon nanotube loading was varied to examine printability, rheological behavior, and thermomechanical response Rheometer, thermomechanical analysis, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and resistivity measurements were used to characterize printed nanocomposite specimens.
11:00 AM
Hydroxyl-Functionalized MWCNT and Nanosilica Reinforced Photocurable Resins for Vat Polymerization: Rahul Sheley1; Sami Gazzaz1; Donavan Brown1; Arish Karowalia1; Tyler Babin1; Jitendra Tate1; 1Texas State University
Digital light processing (DLP) stereolithography enables the precise fabrication of polymer components, but acrylate-based printed substrates have limited mechanical performance and reduced interfacial stability at elevated temperatures. This limitation is critical for metalized parts, where a mismatch in the coefficients of thermal expansion between the polymer substrate and the nickel coating can promote coating failure. This study develops a photocurable nanocomposite resin reinforced with nanosilica and hydroxyl-functionalized multi-walled carbon nanotubes to improve the mechanical, electrical, and thermal performance of DLP-printed substrates. The resin system consists of bisphenol A epoxy diacrylate as the base oligomer and trimethylolpropane triacrylate as the reactive diluent. Nanosilica served as the thermally stable particulate phase, while OH-functionalized multiwall carbon nanotubes were varied as the conductive reinforcement. Rheological, thermal, microstructural, and electrical behavior was evaluated using viscosity testing, thermomechanical analyzer, differential scanning calorimetry, thermogravimetric analyzer, scanning electron microscope, and resistivity measurements for printed nanocomposite coupons.
11:20 AM
Magnetic and Mechanical Properties of SLA-based 3D-printed Magnetic Soft Composite Using a Halbach Cylinder for Inducing Anisotropy: Md Anisul Islam1; Andrew P Haney1; Sonjoy Chandra Debnath1; Ethan Wilfur1; West B Masone1; Brian S Earle1; Bishu Banjara1; Kripa Paudel1; Wilhelmus Geerts1; Jitendra Tate1; 1Texas State University
Magnetic elastomers are a promising approach for artificial muscles and soft robotic systems due to their ability to enable rapid and wireless actuation under external magnetic fields. In this study, an ultra-low modulus photopolymer resin was investigated as a matrix combined with strontium ferrite (SF) particles [SrO(Fe2O3)6]. Composites were fabricated using stereolithography (SLA) with magnetic field-assisted alignment utilizing a Halbach cylinder, enabling control over particle orientation and the formation of anisotropic magnetic properties. Samples were produced with varying SF loadings (1 – 8 wt.%), and magnetic properties were measured using a biaxial vibrating sample magnetometer (VSM). Curing the elastomer composite without a magnetic field resulted in agglomeration without any microstructural alignment of particles as observed with scanning electron microscopy (SEM). However, upon applying a magnetic field, particles aligned in chain-like agglomerates. This work modeled relationships between particle alignment, composition, and composite performance and demonstrated the potential for magnetically actuated applications.
11:40 AM
Laser Powder Bed Fusion of Graphene Nanoplatelet-Reinforced Inconel 718 Metal Matrix Composites: Microstructure and Mechanical Performance: Md Shovon Zahid1; Ola Harrysson1; 1North Carolina State University
Graphene nanoplatelets (GNPs) offer a promising route for enhancing the performance of nickel-based superalloys fabricated by additive manufacturing. In this study, Inconel 718 (IN718) metal matrix composites containing 0.1 wt.% and 0.4 wt.% GNPs were fabricated using laser powder bed fusion (LPBF). The effects of GNP addition on densification behavior, microstructure, hardness, tensile properties, and fatigue performance were investigated and compared with LPBF-processed pure IN718 and conventionally wrought IN718. Relative density measurements were conducted to evaluate processability and defect formation, while microstructural characterization was used to examine grain morphology, melt pool features, and reinforcement distribution. Mechanical testing assessed the influence of GNP content on hardness, strength, ductility, and fatigue resistance. The results provide insights into the feasibility of incorporating graphene-based reinforcements into LPBF-fabricated superalloys and establish processing–structure–property relationships for the development of high-performance metal matrix composites for demanding engineering applications.