Evaluating the effect of variable fiber content on mechanical properties of additively manufactured continuous carbon fiber composites

2020 ◽  
pp. 073168442096321
Author(s):  
Dakota R Hetrick ◽  
Seyed Hamid Reza Sanei ◽  
Charles E Bakis ◽  
Omar Ashour

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.

2016 ◽  
Vol 2 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Hasan Jalilifar ◽  
Fatholla Sajedi ◽  
Sadegh Kazemi

The flexural strength of conventional concrete material is known to be enhanced by incorporating a moderate volume-fraction of randomly distributed fibers. However, there is limited information on describing the influence of fiber volume-fraction on the compressive and flexural strength of recycled coarse aggregate concrete (RCA-C) material. This paper reports on experimental test results of the RCA-C material replaced with 0, 30, 50 and 100% recycled aggregate and 0, 0.5, 1 and 1.5% steel fiber volume fraction. Three-point flexural tests of notched prism specimens were completed. The mechanical properties in compression were characterized using cube specimens. Significant improvement in compressive and flexural strength of RCA-C was found as fiber content increased from 0 to 1.5%. The experimental test results of RCA-C were further evaluated to investigate the influence of fiber content on flexural toughness. According to test results, the addition of steel fibers to RCA-C material appreciably increased the flexural toughness.


2021 ◽  
Vol 1016 ◽  
pp. 151-155
Author(s):  
Keizo Hashimoto ◽  
Jiang Jin

Although metal matrix composites (MMC) for the high temperature structural material have been investigated extensively for many years, applications of MMC have been still limited. Among many combinations between the ceramic fibers and the matrix materials, combination of SiC fiber and TiAl based intermetallic compounds has been expected to be one of the best combination, since both SiC fiber and TiAl have demonstrated the capabilities of the low density heat resistant materials. SiC fiber reinforced TiAl composites have been successfully fabricated using hot press method. Optimum temperature and pressure have been determined. SiC/TiAl composite having relatively low fiber volume fraction shows nearly an ideal elastic property applying the law of mixture. Effects of interface layers on the mechanical properties of composites have been studied in detail. Micro-indentation on a single fiber was carried out to examine the pull out strength of SiC fiber quantitatively. Estimated shear stress on the interface was 145-195MPa, those values are quite reasonable since the tensile strength of TiAl matrix was 420MPa and the maximum shear stress would be the half of tensile strength according to Schmid law. Three-point bending tests have been carried out to evaluate the mechanical properties of composites. Fiber volume fraction 8.9% specimen shows ideal bending stiffness compare with the calculated values based on the low of mixture. Reaction layers and the interface between SiC fiber and TiAl have been analyzed by SEM-EDS and XRD. At least two or more reaction layers have been identified. These reaction layers can be explained based on the Si-Ti-C ternary equilibrium phase diagram at 1373K. Optimum conditions of interface structure will be discussed


2013 ◽  
Vol 2013 (0) ◽  
pp. _J045024-1-_J045024-4
Author(s):  
Kazuma SHIRAISHI ◽  
Sho ISHII ◽  
Atsushi KASAI ◽  
Noriyoshi MIWA ◽  
Yoshitake NISHI

2019 ◽  
Vol 801 ◽  
pp. 276-281
Author(s):  
Peng Hao Wang ◽  
Ronald Sterkenburg ◽  
Garam Kim ◽  
Yu Wei He

Composite materials continue to grow in popularity within the aerospace industry as the preferred material for manufacturing large airframe structures. However, the popularity of composite materials has also led to the increase in composite waste. As the popularity of composite materials continues to grow, the proper management and recycling of these composite waste materials becomes increasingly crucial to the sustainability of the environment. In order to investigate potential recycling techniques for composite waste, a team of Purdue University School of Aviation and Transportation Technology (SATT) faculty and students teamed up to investigate the characteristics of 3D printed recycled carbon fiber. A prototype 3D printed recycled carbon fiber part was used for the study. Through the use of microscopy and ImageJ image analyzing software, the researchers were able to determine the void content, fiber volume fraction, and fiber orientation of the prototype 3D printed recycled carbon fiber part and identified potential improvements to the 3D printing process in order to improve the 3D printed part’s characteristics.


2015 ◽  
Vol 799-800 ◽  
pp. 794-799 ◽  
Author(s):  
Sebti Jaballi ◽  
Imed Miraoui ◽  
Hedi Hassis

This paper focuses on the optimization of flexural strength and thermal conductivity of mortar reinforced with Alfa fibers. Fibers were manually extracted from Alfa leafs to avoid the risk of degradation of mechanical properties. A first group of samples (300 x 300 x 30 mm) having a fiber volume fraction of 0.5 to 1.5% is prepared to measure the thermal conductivity.The second composite family (40 x 40 x 160 mm) cured in a wet chamber is used for measuring its bending strength. The fiber percentage varies from 0.74 to 1,85%.The results show that the thermal conductivity decreases by increasing the fiber content. While the optimal percentage of fiber for the flexural strength is estimated at 1%, corresponding to an increase of 27% in strength.


2005 ◽  
Vol 502 ◽  
pp. 201-204 ◽  
Author(s):  
Tsunemichi Imai ◽  
Shang Li Dong ◽  
Ichinori Shigematsu ◽  
Naobumi Saito ◽  
Kazutaka Suzuki ◽  
...  

The XN-05C/2017, XN-05C/MESO-10 and BGC152/MESO-10 aluminum composites reinforced by low young’s modulus amorphous carbon fiber and particle, respectively, were fabricated by a PM route followed by hot extrusion and rolling in this study. The mechanical properties of the prepared composites were investigated subsequently. The XN-05C/2017 and XN-05C/MESO-10 were found to exhibit low elastic modulus of 50~60GPa within the fiber volume fraction of 0.10~0.15, while the BGC152/MESO-10 shows a data of 50GPa with a particle volume fraction of 0.10. The tensile strength of XN-05C/MESO-10 was evaluated to be 400~600MPa in the case of Vf=0.10~0.15, and become to decease with increasing fiber volume fraction. Damping application would be a potential consideration for the amorphous carbon fiber reinforced aluminum composites.


2021 ◽  
pp. 002199832110047
Author(s):  
Mahmoud Mohamed ◽  
Siddhartha Brahma ◽  
Haibin Ning ◽  
Selvum Pillay

Fiber prestressing during matrix curing can significantly improve the mechanical properties of fiber-reinforced polymer composites. One primary reason behind this improvement is the generated compressive residual stress within the cured matrix, which impedes cracks initiation and propagation. However, the prestressing force might diminish progressively with time due to the creep of the compressed matrix and the relaxation of the tensioned fiber. As a result, the initial compressive residual stress and the acquired improvement in mechanical properties are prone to decline over time. Therefore, it is necessary to evaluate the mechanical properties of the prestressed composites as time proceeds. This study monitors the change in the tensile and flexural properties of unidirectional prestressed glass fiber reinforced epoxy composites over a period of 12 months after manufacturing. The composites were prepared using three different fiber volume fractions 25%, 30%, and 40%. The results of mechanical testing showed that the prestressed composites acquired an initial increase up to 29% in the tensile properties and up to 32% in the flexural properties compared to the non-prestressed counterparts. Throughout the 12 months of study, the initial increase in both tensile and flexural strength showed a progressive reduction. The loss ratio of the initial increase was observed to be inversely proportional to the fiber volume fraction. For the prestressed composites fabricated with 25%, 30%, and 40% fiber volume fraction, the initial increase in tensile and flexural strength dropped by 29%, 25%, and 17%, respectively and by 34%, 26%, and 21%, respectively at the end of the study. Approximately 50% of the total loss took place over the first month after the manufacture, while after the sixth month, the reduction in mechanical properties became insignificant. Tensile modulus started to show a very slight reduction after the fourth/sixth month, while the flexural modulus reduction was observed from the beginning. Although the prestressed composites displayed time-dependent losses, their long-term mechanical properties still outperformed the non-prestressed counterparts.


2012 ◽  
Vol 583 ◽  
pp. 150-153
Author(s):  
Qian Liu ◽  
Xiao Yuan Pei ◽  
Jia Lu Li

The modal properties of carbon fiber woven fabric (with fiber orientation of 45°/-45°) / epoxy resin composites with different fiber volume fraction were studied by using single input and single output free vibration of cantilever beam hammering modal analysis method. The effect of different fiber volume fraction on the modal parameters of laminated composites was analyzed. The experimental results show that with the fiber volume fraction increasing, the natural frequency of laminated composites becomes larger and damping ratio becomes smaller. The fiber volume fraction smaller, the peak value of natural frequency becomes lower and the attenuating degree of acceleration amplitude becomes faster.


2021 ◽  
pp. 002199832110112
Author(s):  
Qing Yang Steve Wu ◽  
Nan Zhang ◽  
Weng Heng Liew ◽  
Vincent Lim ◽  
Xiping Ni ◽  
...  

Propagation of ultrasonic wave in Carbon Fiber Reinforced Polymer (CFRP) is greatly influenced by the material’s matrix, resins and fiber volume ratio. Laser ultrasonic broadband spectral technique has been demonstrated for porosity and fiber volume ratio extraction on unidirection aligned CFRP laminates. Porosity in the matrix materials can be calculated by longitudinal wave attenuation and accurate fiber volume ratio can be derived by combined velocity through the high strength carbon fiber and the matrix material with further consideration of porosity effects. The results have been benchmarked by pulse-echo ultrasonic tests, gas pycnometer and thermal gravimetric analysis (TGA). The potentials and advantages of the laser ultrasonic technique as a non-destructive evaluation method for CFRP carbon fiber volume fraction evaluation were demonstrated.


Sign in / Sign up

Export Citation Format

Share Document