Damage mechanisms characterization of flax fibers–reinforced composites with interleaved natural viscoelastic layer using acoustic emission analysis

2019 ◽  
Vol 53 (18) ◽  
pp. 2623-2637 ◽  
Author(s):  
Abderrahim El Mahi ◽  
Hajer Daoud ◽  
Jean-Luc Rebiere ◽  
Isabelle Gimenez ◽  
Mohamed Taktak ◽  
...  
Keyword(s):  
Acoustic Emission ◽  
Mechanical Behavior ◽  
Flax Fiber ◽  
Fiber Reinforced Composites ◽  
Viscoelastic Layer ◽  
Uniaxial Tensile ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Viscoelastic Composite ◽  
The Impact

In this paper, the static and fatigue behavior of flax fiber-reinforced composites with and without an interleaved natural viscoelastic layer are investigated. Viscoelastic composite plates consist of a soft natural viscoelastic layer which is confined between two identical flax fiber reinforced composites. Different stacking sequences of specimens are tested with uniaxial tensile loading until failure. The mechanical behavior and the acoustic activity of damage sources in various configurations with and without a viscoelastic layer are compared. The analysis of acoustic emission signals and the macroscopic and microscopic observations led to the identification of the main acoustic signatures of different damage modes dominant in each type of composites (with and without a viscoelastic layer). These results allow better identification of the influence of the impact of a viscoelastic layer on the mechanical behavior of different composites. In addition, static and fatigue flexural behavior of unidirectional composites with and without viscoelastic layer are characterized in 3-point bending tests. The effects of viscoelastic layer on the stiffness, hysteresis loops, and loss factor are studied for various numbers of cycles during cyclic fatigue.

scholarly journals Effect of Temperature and Water Absorption on Low-Velocity Impact Damage of Composites with Multi-Layer Structured Flax Fiber

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 453 ◽  
Author(s):  
Yiou Shen ◽  
Junjie Zhong ◽  
Shenming Cai ◽  
Hao Ma ◽  
Zehua Qu ◽  
...  
Keyword(s):  
Water Absorption ◽  
Structural Damage ◽  
Impact Damage ◽  
Damage Threshold ◽  
Flax Fiber ◽  
Fiber Reinforced Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Damage Resistance ◽  
The Impact

Temperature and moisture can cause degradation to the impact properties of plant fiber-based composites owing to their complex chemical composition and multi-layer microstructure. This study focused on experimental characterization of the effect of important influencing factors, including manufacturing process temperature, exposure temperature, and water absorption, on the impact damage threshold and damage mechanisms of flax fiber reinforced composites. Firstly, serious reduction on the impact damage threshold and damage resistance was observed, this indicated excessive temperature can cause chemical decomposition and structural damage to flax fiber. It was also shown that a moderate high temperature resulted in lower impact damage threshold. Moreover, a small amount of water absorption could slightly improve the damage threshold load and the damage resistance. However, more water uptake caused severe degradation on the composite interface and structural damage of flax fiber, which reduced the impact performance of flax fiber reinforced composites.

Numerical and Experimental Characterization of the Dynamic Properties of Flax Fiber Reinforced Composites

2016 ◽  
Vol 08 (05) ◽  
pp. 1650068 ◽  
Author(s):  
Hajer Daoud ◽  
Jean-Luc Rebière ◽  
Amine Makni ◽  
Mohamed Taktak ◽  
Abderrahim El Mahi ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Element Model ◽  
Flax Fiber ◽  
Fiber Reinforced Composites ◽  
Viscoelastic Layer ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Damping Behavior ◽  
Modal Damping ◽  
Vibration Tests

In this paper, the damping properties of flax fiber reinforced composites were investigated. Throughout a series of resonance vibration tests, the natural frequencies and the modal damping were evaluated. A numerical modelling was also produced by using a finite element model to determine the energies dissipated in each layer of the laminate structure in order to calculate the damping factors. The results obtained for the dynamic properties of flax fiber reinforced composites from experimental data and numerical analysis method show close agreement. The effect of fiber orientations on the damping behavior for this material was investigated. Another part of our work was to insert a thin viscoelastic layer within the flax fiber laminate. The interposition of this viscoelastic layer had a significant influence on the vibration behavior, bending stiffness and damping factors.

Effect of Velocity on the Impact Resistance of Woven Jute Fiber Reinforced Composites

2013 ◽  
Vol 465-466 ◽  
pp. 1277-1281 ◽  
Author(s):  
Al Emran Ismail ◽  
Muhd Hafeez Zainulabidin ◽  
Mohd Nazrul Roslan ◽  
Abdul Latif Mohd Tobi ◽  
Nik Hisyamudin Muhd Nor
Keyword(s):  
Failure Mechanisms ◽  
Impact Resistance ◽  
Fiber Reinforced Composites ◽  
Jute Fiber ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Wide Range ◽  
Force Time ◽  
Type Of Failure ◽  
The Impact

is present project investigated the impact penetration response of woven jute fiber reinforced composites subjected to wide range of low impact velocities. Hand layout woven jute fibers are thermally compressed to ensure no internal defects formed in the composites. Six layers of woven jutes are stacked together using different fiber orientations [0/q/0]s. Low impact velocities are used ranging between 5 – 20 m/s. Force-time, force-displacement and energy-time curves are obtained automatically during the impact tests. The results are then discussed with considering the composite fragmentations and failure mechanisms. It is found that 00composite orientations capable to absorb sufficiently impact energy for 5 m/s but not for velocity greater than 10 m/s. When fiber orientations used between 15 – 450, the composite impact resistance increased indicating two significant peak forces. These peak forces represent different type of failure mechanisms occurred during the striker progresses.

Sign in / Sign up

Export Citation Format

Share Document