Comparative Screening of the Structural and Thermomechanical Properties of FDM Filaments Comprising Thermoplastics Loaded with Cellulose, Carbon and Glass Fibers

Abstract

Additive manufacturing (AM) has been rapidly growing for a decade in both consumer and industrial products. Fused deposition modeling (FDM), one of the most widely used additive manufacturing methods, owes its popularity to cost effectiveness in material and equipment investment. Current efforts are aimed toward high load-bearing capacity at low material costs. However, the mechanical reliability of end-products derived from these compositions and their dependence on microstructural effects, have remained as major limitations. This is mainly owing to the unknown mechanics of the materials, including the reinforcing or filler components and their interphase/interface compatibility. For this reason, here we investigate the most relevant commercial polymeric materials used in composite filaments, associated phases and the characterization protocols that can guide component selection, screening and troubleshooting. We first present thermal analyses (thermogravimetric, TGA and differential scanning calorimetry, DSC) in relation to the constituent fractions and identify the type of polymer for uses in filaments production. The influence of various fillers is unveiled in terms of the crystallization behavior of derived 3D-printed parts. To understand the microstructural effects on the material strength, we carry out a series of tensile experiments on 3-D printed dog-bone shaped specimens following ISO standards. Simultaneously, real-time thermal energy dissipation and damage analyses are applied by using infrared measurements at fast frame rates (200 Hz) and high thermal resolution (50 mK). The failure regions of each specimen are examined via optical, scanning and transmission electron microscopies. The results are used to reveal new insights into the size, morphology and distribution of the constituents and interphases of polymer filaments for FDM. The present study represents advancement in the field of composite filament fabrication, with potential impact in the market of additive manufacturing.

Reliability-Based Evaluation of the Suitability of Polymers for Additive Manufacturing Intended for Extreme Operating Conditions

“…In Stage C, an integrated evaluation using a reliability-based approach is carried out using the calculations obtained in stages A and B. Since it is essential to predict reliability of end-products because this is one of their major limitations [ 69 ].…”

Creep and Recovery Behavior of Continuous Fiber-Reinforced 3DP Composites

“…However, physical and mechanical properties of polymers have hindered their utilization due to inferior properties compared to conventional materials such as metals and alloys. Several studies reported improved mechanical properties of polymers through synthetic or natural fibers reinforcement [ 5 , 6 , 7 ]. However, 3DP of continuous fiber-reinforced polymer (CFRP) composites is still a challenge.…”

Thermoplastic Cellulose-Based Compound for Additive Manufacturing

“…The stiffness properties of PLA-based composites are typically enhanced by adding different kind of fillers such as metal powder, carbon or glass-fibers, cellulose, microcellulose, wood and agro-fibers [ 23 , 24 ]. However, at the same time, tensile and impact strength properties are decreasing [ 23 , 25 , 26 , 27 , 28 ]. Also, due to quite low glass transition temperature, typically below 60 °C, the suitability of PLA-composite in many applications is limited.…”