Effect of polyethylene fiber content on workability and mechanical-anisotropic properties of 3D printed ultra-high ductile concrete

Fiber volume fraction is a driving factor in mechanical properties of composites. Micromechanical models are typically used to predict the effective properties of composites with different fiber volume fractions. Since the microstructure of 3D-printed composites is intrinsically different than conventional composites, such predictions need to be evaluated for 3D-printed composites. This investigation evaluates the ability of the Voigt, Reuss, and Halpin–Tsai models to capture the dependence of modulus and strength of 3D-printed composites on varying fiber volume fraction. Tensile coupons were printed with continuous carbon fiber-reinforced Onyx matrix using a Markforged Mark Two printer. Specimens were printed at five different volume fractions with unidirectional fibers oriented at either [Formula: see text] to obtain longitudinal, shear, and transverse properties, respectively. It is shown that the Voigt model provides an excellent fit for the longitudinal tensile strength and a reasonable fit for the longitudinal modulus with varied fiber content. For the transverse direction, while the Reuss model fails to capture the transverse modulus trend, the Halpin–Tsai model provides a reasonable fit as it incorporates more experimental parameters. Like conventional composites, addition of fibers degrades the transverse strength, and the transverse strength decreases with increasing fiber volume fraction. The shear modulus variation with fiber content could not be fitted reasonably with either Halpin–Tsai model or Reuss model.

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Determination of Fiber Content in 3D Printed Composite Parts Using Image Analysis

IEEE Embedded Systems Letters ◽

10.1109/les.2022.3140417 ◽

2022 ◽

pp. 1-1

Author(s):

Harsh Srivastava ◽

Hammond Pearce ◽

Gary Mac ◽

Nikhil Gupta

Keyword(s):

Image Analysis ◽

Fiber Content ◽

3D Printed

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Maximizing the Performance of 3D Printed Fiber-Reinforced Composites

Journal of Composites Science ◽

10.3390/jcs5050136 ◽

2021 ◽

Vol 5 (5) ◽

pp. 136

Author(s):

S M Fijul Kabir ◽

Kavita Mathur ◽

Abdel-Fattah M. Seyam

Keyword(s):

3D Printing ◽

Fiber Content ◽

Structural Defects ◽

Favorable Effect ◽

Fiber Reinforced ◽

Printing Technology ◽

Premature Failure ◽

3D Printing Technology ◽

3D Printed ◽

3D Orthogonal Woven

Fiber-reinforced 3D printing technology offers significant improvement in the mechanical properties of the resulting composites relative to 3D printed (3DP) polymer-based composites. However, 3DP fiber-reinforced composite structures suffer from low fiber content compared to the traditional composite, such as 3D orthogonal woven preforms solidified with vacuum assisted resin transfer molding (VARTM) that impedes their high-performance applications such as in aerospace, automobile, marine and building industries. The present research included fabrication of 3DP fiberglass-reinforced nylon composites, with maximum possible fiber content dictated by the current 3D printing technology at varying fiber orientations (such as 0/0, 0/90, ±45 and 0/45/90/−45) and characterizing their microstructural and performance properties, such as tensile and impact resistance (Drop-weight, Izod and Charpy). Results indicated that fiber orientation with maximum fiber content have tremendous effect on the improvement of the performance of the 3DP composites, even though they inherently contain structural defects in terms of voids resulting in premature failure of the composites. Benchmarking the results with VARTM 3D orthogonal woven (3DOW) composites revealed that 3DP composites had slightly lower tensile strength due to poor matrix infusion and voids between adjacent fiber layers/raster, and delamination due to lack of through-thickness reinforcement, but excellent impact strength (224% more strong) due to favorable effect of structural voids and having a laminated structure developed in layer-by-layer fashion.

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Influence of Flour and Fat Type on Dough Rheology and Technological Characteristics of 3D-Printed Cookies

Foods ◽

10.3390/foods10010193 ◽

2021 ◽

Vol 10 (1) ◽

pp. 193

Author(s):

Tomislava Vukušić Pavičić ◽

Tomislava Grgić ◽

Mia Ivanov ◽

Dubravka Novotni ◽

Zoran Herceg

Keyword(s):

Olive Oil ◽

Dietary Fiber ◽

Quality Parameters ◽

Fiber Content ◽

Dough Rheology ◽

Color Line ◽

High Fiber ◽

Printing Quality ◽

Cookie Quality ◽

3D Printed

In this study, we designed high fiber cookie recipe without using additives by means of extrusion-based 3D printing. We aimed to relate printing quality and cookie physical properties with dough rheology and dietary fiber content depending on the flour (oat, rye, rice, and carob flour) and fat type (olive oil or butter). The flour choice influenced all cookie quality parameters: baking loss, color, line height and width, and dietary fiber content. Results indicated that lower baking loss and better printing quality were obtained for cookie dough containing olive oil, which had higher viscosity and consistency coefficient compared with dough containing butter. Cookies with olive oil in which part of the oat flour was replaced with rye and carob flour were printed with high accuracy (≥98%), close to the ideal 3D shape. Overall, this study demonstrates the importance of selecting fat and particularly flour, as well as the extrusion rate on the quality and repeatability of 3D-printed cookies.

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