Effective enhancement of the mechanical properties of macroscopic single-walled carbon nanotube fibers by pressure treatment

RSC Advances ◽  
2016 ◽  
Vol 6 (99) ◽  
pp. 97012-97017 ◽  
Author(s):  
Gu Hou ◽  
Gang Wang ◽  
Ya Deng ◽  
Jian Zhang ◽  
Jean Pierre Nshimiyimana ◽  
...  

A SWNTs cylindrical fiber is fabricated with diamond wire drawing dies and the SWNT ribbon-like fiber is obtained by pressure treatment. The tensile strength and Young's modulus of ribbon-like fibers can be enhanced with a maximum factor about 55.

Nanoscale ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 4585-4590 ◽  
Author(s):  
Chao Zhang ◽  
Yanhui Song ◽  
Huichao Zhang ◽  
Bo Lv ◽  
Jian Qiao ◽  
...  

Mechanical properties of tensile strength and Young's modulus of CNT fibers were obtained at temperatures from −196 °C to 2400 °C.


2022 ◽  
Vol 17 (1) ◽  
Author(s):  
Xian Shi ◽  
Xiaoqiao He ◽  
Ligang Sun ◽  
Xuefeng Liu

Abstract Networks based on carbon nanotube (CNT) have been widely utilized to fabricate flexible electronic devices, but defects inevitably exist in these structures. In this study, we investigate the influence of the CNT-unit defects on the mechanical properties of a honeycomb CNT-based network, super carbon nanotube (SCNT), through molecular dynamics simulations. Results show that tensile strengths of the defective SCNTs are affected by the defect number, distribution continuity and orientation. Single-defect brings 0 ~ 25% reduction of the tensile strength with the dependency on defect position and the reduction is over 50% when the defect number increases to three. The distribution continuity induces up to 20% differences of tensile strengths for SCNTs with the same defect number. A smaller arranging angle of defects to the tensile direction leads to a higher tensile strength. Defective SCNTs possess various modes of stress concentration with different concentration degrees under the combined effect of defect number, arranging direction and continuity, for which the underlying mechanism can be explained by the effective crack length of the fracture mechanics. Fundamentally, the force transmission mode of the SCNT controls the influence of defects and the cases that breaking more force transmission paths cause larger decreases of tensile strengths. Defects are non-negligible factors of the mechanical properties of CNT-based networks and understanding the influence of defects on CNT-based networks is valuable to achieve the proper design of CNT-based electronic devices with better performances. Graphical Abstract


2017 ◽  
Vol 51 (12) ◽  
pp. 1693-1701 ◽  
Author(s):  
EA Zakharychev ◽  
EN Razov ◽  
Yu D Semchikov ◽  
NS Zakharycheva ◽  
MA Kabina

This paper investigates the structure, length, and percentage of functional groups of multi-walled carbon nanotubes (CNT) depending on the time taken for functionalization in HNO3 and H2SO4 mixture. The carbon nanotube content and influence of functionalization time on mechanical properties of polymer composite materials based on epoxy matrix are studied. The extreme dependencies of mechanical properties of carbon nanotube functionalization time of polymer composites were established. The rise in tensile strength of obtained composites reaches 102% and elastic modulus reaches 227% as compared to that of unfilled polymer. The composites exhibited best mechanical properties by including carbon nanotube with 0.5 h functionalization time.


2020 ◽  
Author(s):  
Daniel Mählich ◽  
Oliver Eberhardt ◽  
Thomas Wallmersperger

AbstractDue to their outstanding mechanical properties, carbon nanotubes (CNTs) are very promising materials for further applications in the field of lightweight construction. Carbon nanotube fibers, whose structure consists of a multitude of load-bearing carbon nanotube bundles interconnected by threads, are an excellent possibility to utilize these properties as engineering material. In the present research, a new method for the prediction of the mechanical properties of carbon nanotube bundles is presented. Within this, the complex structure is transformed into a simplified model based on suitable assumptions. Several parameters of the bundle are taken into account such as different types of nanotubes and various nanotube lengths. The model is applied to different configurations of carbon nanotube bundles by using a molecular mechanics approach. The interactions between the nanotubes are investigated by analyzing the Lennard–Jones potential in a virtual tensile loading test. For different configurations, the resulting forces and stresses are obtained. The results give a clear insight into the influencing parameters and demonstrate their effect on the mechanical behavior. In conclusion, the present approach is an excellent method to analyze the mechanical behavior of CNT bundles.


2020 ◽  
pp. 002199832095354 ◽  
Author(s):  
Tien-Thinh Le

This paper is devoted to the development and construction of a practical Machine Learning (ML)-based model for the prediction of tensile strength of polymer carbon nanotube (CNTs) composites. To this end, a database was compiled from the available literature, composed of 11 input variables. The input variables for predicting tensile strength of nanocomposites were selected for the following main reasons: (i) type of polymer matrix, (ii) mechanical properties of polymer matrix, (iii) physical characteristics of CNTs, (iv) mechanical properties of CNTs and (v) incorporation parameters such as CNT weight fraction, CNT surface modification method and processing method. As the problem of prediction is highly dimensional (with 11 dimensions), the Gaussian Process Regression (GPR) model was selected and optimized by means of a parametric study. The correlation coefficient (R), Willmott’s index of agreement (IA), slope of regression, Mean Absolute Percentage Error (MAPE), Root Mean Squared Error (RMSE) and Mean Absolute Error (MAE) were employed as error measurement criteria when training the GPR model. The GPR model exhibited good performance for both training and testing parts (RMSE = 5.982 and 5.327 MPa, MAE = 3.447 and 3.539 MPa, respectively). In addition, uncertainty analysis was also applied to estimate the prediction confidence intervals. Finally, the prediction capability of the GPR model with different ranges of values of input variables was investigated and discussed. For practical application, a Graphical User Interface (GUI) was developed in Matlab for predicting the tensile strength of nanocomposites.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Ling Liu ◽  
Qiaoxin Yang ◽  
Jingwen Shen

Porous carbon nanotube (CNT) buckypapers (BPs) with various porosities were obtained by using a positive pressure filtration method. The porosity of the BPs fell into a wide range of 11.3–39.3%. Electrical conductivities and tensile mechanical properties of the prepared BPs were then measured and correlated with the porosity of the CNT BPs. Results demonstrated that the conductivities, tensile strength, and elastic modulus of the BPs could decrease by increasing their porosity. The elongation at break of the BPs on the other hand did increase significantly, suggesting improved toughness of the BPs. The obtained electrical conductivity and tensile strength of the porous BPs can reach nearly 0.6 S/m and 26 MPa, respectively, which may be potentially useful in composites reinforcement and conductive materials.


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