A new method for Poisson’s ratio measurement with time-of-flight technique: application to the preliminary design of smart composite structures

2019 ◽  
Author(s):  
Xianlong Chen ◽  
Yann Meyer ◽  
Rémy Lachat ◽  
Morvan Ouisse
Keyword(s):  
Poisson’S Ratio ◽  
Composite Structures ◽  
Time Of Flight ◽  
New Method ◽  
Poisson's Ratio ◽  
Preliminary Design ◽  
Smart Composite ◽  
Ratio Measurement ◽  
Smart Composite Structures

Vibrations of Functionally Graded Shells

2007 ◽  
Author(s):  
Serge Abrate
Keyword(s):  
Composite Material ◽  
Modulus Of Elasticity ◽  
Poisson’S Ratio ◽  
Functionally Graded ◽  
New Method ◽  
Poisson's Ratio ◽  
Tabular Form ◽  
Graded Structures ◽  
Functionally Graded Structures

The behavior of functionally graded structures has received a great deal of attention in recent years. Usually, these structures are made out of a composite material with a modulus of elasticity, a Poisson’s ratio, and a density that vary through the thickness. The non-uniformity through the thickness introduces coupling between the transverse deformations and the deformations of the mid-surface. Previous publications have shown how to account for these added complexities and have presented extensive results in tabular form. In this article, available results are used to show that the behavior of functionally graded shells is similar to that of homogeneous isotropic shells. It is well known that for isotropic shells, results can be presented in non-dimensional form so that, once results are obtained for one material, they can be simply scaled to obtain the corresponding results for shells made out of another material. The same can then be done for functionally graded shells. In addition, if functionally graded shells behave like homogeneous shells, no new method of analysis is required. The second part of the paper examines why this is true.

Finite Element Martensite Ratio Derivation on NiTi via Measurable Criteria of Strain Rate

2009 ◽  
Author(s):  
Abbas Amini ◽  
Hamid Mehdigholi ◽  
Mohammad Elahinia
Keyword(s):  
Mathematical Model ◽  
Strain Rate ◽  
Composite Structures ◽  
High Sensitivity ◽  
Smart Composite ◽  
Rate Dependency ◽  
Smart Composites ◽  
Measurable Amount ◽  
Macro Scale ◽  
Smart Composite Structures

The shape memory alloys (SMAs) and smart composites have a large use in high and low level industry, while a lot of research is being done in this field. The existence of smart composite structures is because of the advance mechanical benefits of the above materials. This work refers to dynamic and quasi static nonlinear explanation of these materials. After mathematical model consideration on the rate of strain, a model which is about martensite ratio of NiTi has been presented. This work has been done because of the high sensitivity of these materials to strain rate and use of visual and measurable engineering criteria to access other variables. As the martensite ratio is not engineering measurable amount, it needs to have macro scale property to measure this important nano scale criteria. Relative experiments are done to show the rate dependency of NiTi.

scholarly journals Additive Manufacturing of Smart Composite Structures Based on Flexinol Wires

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 499
Author(s):  
Olaf Dudek ◽  
Wojciech Klein ◽  
Damian Gąsiorek ◽  
Mariusz Pawlak
Keyword(s):  
Shape Memory ◽  
Composite Structure ◽  
Composite Structures ◽  
Shape Memory Material ◽  
Smart Composite ◽  
Memory Material ◽  
Current Voltage ◽  
Smart Composite Structures ◽  
3D Printed ◽  
Special Approach

3D printing of a composite structure with shape memory materials requires a special approach to the subject, at the stage of the design and printing process. This paper presents the design steps during the development of a 3D-printed composite structure with shape memory material. The connection points between the SMA fibers and the printer filament are developed in the MATLAB environment. Finite element method is used to simulate the shortening of the shape memory material under the influence of temperature and its effect on the printed polymer material is presented. In the MATLAB environment, evolutionary algorithms were used to determine the shape of the SMA fiber alignment. This work demonstrates the use of shape memory effect in 3D printed smart composite structures, where the component takes a predetermined shape. The structure obtained as a result of such printing changes with the heat generated by the current voltage, making it the desired fourth dimension.

Biomimetic composites inspired by venous leaf

2017 ◽  
Vol 52 (3) ◽  
pp. 361-372 ◽  
Author(s):  
Gongdai Liu ◽  
R Ghosh ◽  
A Vaziri ◽  
A Hossieni ◽  
D Mousanezhad ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Yield Stress ◽  
Poisson’S Ratio ◽  
Composite Structures ◽  
Volume Fraction ◽  
Matrix Material ◽  
Poisson's Ratio ◽  
Fiber Volume ◽  
Young’S Moduli

A typical plant leaf can be idealized as a composite having three principal fibers: the central mid-fiber corresponding to the mid-rib, straight parallel secondary fibers attached to the mid-fiber representing the secondary veins, and then another set of parallel fibers emanating from the secondary fibers mimicking the tertiary fibers embedded in a matrix material. This paper introduces a biomimetic composite design inspired by the morphology of venous leafs and investigates the effects of venation morphologies on the in-plane mechanical properties of the biomimetic composites using finite element method. The mechanical properties such as Young’s moduli, Poisson’s ratio, and yield stress under uniaxial loading of the resultant composite structures was studied and the effect of different fiber architectures on these properties was investigated. To this end, two broad types of architectures were used both having similar central main fiber but differing in either having only secondary fibers or additional tertiary fibers. The fiber and matrix volume fractions were kept constant and a comparative parametric study was carried out by varying the inclination of the secondary fibers. The results show that the elastic modulus of composite in the direction of main fiber increases linearly with increasing the angle of the secondary fibers. Furthermore, the elastic modulus is enhanced if the secondary fibers are closed, which mimics composites with closed cellular fibers. In contrast, the elastic modulus of composites normal to the main fiber ( x direction) exponentially decreases with the increase of the angle of the secondary fibers and it is little affected by having secondary fibers closed. Similar results were obtained for the yield stress of the composites. The results also indicate that Poisson’s ratio linearly increases with the secondary fiber angle. The results also show that for a constant fiber volume fraction, addition of various tertiary fibers may not significantly enhance the mechanical properties of the composites. The mechanical properties of the composites are mainly dominated by the secondary fibers. Finally, a simple model was proposed to predict these behaviors.

Development of fibre optic ingress/egress methods for smart composite structures

2000 ◽  
Vol 9 (2) ◽  
pp. 149-156 ◽  
Author(s):  
H K Kang ◽  
J W Park ◽  
C Y Ryu ◽  
C S Hong ◽  
C G Kim
Keyword(s):  
Composite Structures ◽  
Fibre Optic ◽  
Smart Composite ◽  
Smart Composite Structures

Health monitoring of smart composite structures using ultrasonic guided waves

2000 ◽  
Author(s):  
Thomas Monnier ◽  
Philippe Guy ◽  
Yves Jayet ◽  
Jean-Claude Baboux ◽  
Michelle Salvia
Keyword(s):  
Health Monitoring ◽  
Composite Structures ◽  
Guided Waves ◽  
Ultrasonic Guided Waves ◽  
Smart Composite ◽  
Smart Composite Structures

Mechanical Properties of Biomimetic Leaf Composite

2016 ◽  
Author(s):  
Hamid Nayeb Hashemi ◽  
Gongdai Liu ◽  
Ashkan Vaziri ◽  
Masoud Olia ◽  
Ranajay Ghosh
Keyword(s):  
Mechanical Properties ◽  
Yield Stress ◽  
Poisson’S Ratio ◽  
Composite Structures ◽  
Volume Fraction ◽  
Fiber Composite ◽  
Poisson's Ratio ◽  
Closed Cell ◽  
Cell Architecture ◽  
The Matrix

In this paper, we mimic the venous morphology of a typical plant leaf into a fiber composite structure where the veins are replaced by stiff fibers and the rest of the leaf is idealized as an elastic perfectly plastic polymeric matrix. The variegated venations found in nature are idealized into three principal fibers — the central mid-fiber corresponding to the mid-rib, straight parallel secondary fibers attached to the mid-fiber representing the secondary veins and then another set of parallel fibers emanating from the secondary fibers mimicking the tertiary veins of a typical leaf. The tertiary fibers do not interconnect the secondary fibers in our present study. We carry out finite element (FE) based computational investigation of the mechanical properties such as Young’s moduli, Poisson’s ratio and yield stress under uniaxial loading of the resultant composite structures and study the effect of different fiber architectures. To this end, we use two broad types of architectures both having similar central main fiber but differing in either having only secondary fibers or additional tertiary fibers. The fiber and matrix volume fractions are kept constant and a comparative parametric study is carried out by varying the inclination of the secondary fibers. We find significant effect of fiber inclination on the overall mechanical properties of the composites with higher fiber angles transitioning the composite increasingly into a matrix-dominated response. We also find that in general, composites with only secondary fibers are stiffer with closed cell architecture of the secondary fibers. The closed cell architecture also arrested the yield stress decrease and Poisson’s ratio increase at higher fiber angles thereby mitigating the transition into the matrix dominated mode. The addition of tertiary fibers also had a pronounced effect in arresting this transition into the matrix dominated mode. However, it was found that indiscriminate addition of tertiary fibers may not provide desired additional stiffness for fixed volume fraction of constituents. In conclusion, introducing a leaf-mimicking topology in fiber architecture can provide significant additional degrees of tunability in design of these composite structures.

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