Carbon Nanotube-Based Composite Filaments for 3D Printing of Structural and Conductive Elements

Abstract

In this publication, we describe the process of fabrication and the analysis of the properties of nanocomposite filaments based on carbon nanotubes and acrylonitrile butadiene styrene (ABS) polymer for fused deposition modeling (FDM) additive manufacturing. Polymer granulate was mixed and extruded with a filling fraction of 0.99, 1.96, 4.76, 9.09 wt.% of CNTs (carbon nanotubes) to fabricate composite filaments with a diameter of 1.75 mm. Detailed mechanical and electrical investigations of printed test samples were performed. The results demonstrate that CNT content has a significant influence on mechanical properties and electrical conductivity of printed samples. Printed samples obtained from high CNT content composites exhibited an improvement in the tensile strength by 12.6%. Measurements of nanocomposites’ electrical properties exhibited non-linear relation between the supply voltage and measured sample resistivity. This effect can be attributed to the semiconductor nature of the CNT functional phase and the occurrence of a tunnelling effect in percolation network. Detailed I–V characteristics related to the amount of CNTs in the composite and the supply voltage influence are also presented. At a constant voltage value, the average resistivity of the printed elements is 2.5 Ωm for 4.76 wt.% CNT and 0.15 Ωm for 9.09 wt.% CNT, respectively. These results demonstrate that ABS/CNT composites are a promising functional material for FDM additive fabrication of structural elements, but also structural electronics and sensors.

Design of an Atypical Construction of Equipment for Additive Manufacturing with a Conceptual Solution of a Printhead Intended for the Use of Recycled Plastic Materials

“…Due to the design and application of the solution to a specific type of atypical production of models, it is necessary to determine the proposed equipment's basic requirements. Given the knowledge already gained related to structures, control, kinematics and data processing for FDM technology, we can create a list of basic requirements for creating an atypical structure [23]. These requirements are completed to develop an atypical device designed for non-planar 3D printing.…”

Fabrication of High-Performance CNT Reinforced Polymer Composite for Additive Manufacturing by Phase Inversion Technique

“…The FFF is an extrusion-based process. The final component is produced by superposing layers of extruded filaments [4,5].…”

“…In addition, the printed part itself has some constraints due to insufficient adhesion between subsequent layers and internal porosities. Accordingly, a printout with 100% filling is almost impossible [4,6].…”

“…Generally, the surface of glass and carbon fibers [7][8][9] is chemically modified to enhance the mechanical properties of FFF printed parts. Therefore, the employment of a proper matrix and reinforcement may cause an improvement in the mechanical properties and the achievement of other properties such as high thermal and electrical conductivity [4].…”

Coupled Flexural-Electrical Evaluation of Additively Manufactured Multifunctional Composites at Ambient Temperature

“…The FFF is used for advanced manufacturing of advanced material system with a degree of tailorability compared to the traditional manufacturing techniques [2]. Four-point flexural and tensile tests were conducted on continuous carbon fiber-reinforced composites (CCFRP) test coupons additively manufactured using fused deposition modeling (FDM) [3] to assess monofunctional flexural and tensile properties [4]. FDM was used for 3D printing of the CCFRP with concentric and isotropic carbon fiber infill patterns [4].…”