Dayang Laila Abang Abdul Majid

Hybrid Composite Laminates Reinforced with Kevlar/Carbon/Glass Woven Fabrics for Ballistic Impact Testing

Current study reported a facile method to investigate the effects of stacking sequence layers of hybrid composite materials on ballistic energy absorption by running the ballistic test at the high velocity ballistic impact conditions. The velocity and absorbed energy were accordingly calculated as well. The specimens were fabricated from Kevlar, carbon, and glass woven fabrics and resin and were experimentally investigated under impact conditions. All the specimens possessed equal mass, shape, and density; nevertheless, the layers were ordered in different stacking sequence. After running the ballistic test at the same conditions, the final velocities of the cylindrical AISI 4340 Steel pellet showed how much energy was absorbed by the samples. The energy absorption of each sample through the ballistic impact was calculated; accordingly, the proper ballistic impact resistance materials could be found by conducting the test. This paper can be further studied in order to characterise the material properties for the different layers.

The Effects of Stacking Sequence Layers of Hybrid Composite Materials in Energy Absorption under the High Velocity Ballistic Impact Conditions: An Experimental Investigation

In the current study, the effects of stacking sequence layers of hybrid composite materials on ballistic energy absorption, which were fabricated from Kevlar, carbon, glass fibres, and resin have been experimentally investigated at the high velocity ballistic impact conditions. All the samples have equal mass, shape, and density, nevertheless, they have different stacking sequence layers. After running the ballistic test in the same conditions, the final velocities of the bullets showed that how much energy absorbed by the samples. The energy absorption of each sample through the ballistic impact has been calculated, accordingly, the decent ballistic impact resistance materials could be found by conducting the test. This paper can be further studied in order to characterize the material properties.

High Velocity Impact Damage Analysis for Glass Epoxy-Laminated Plates

The ultimate objective of the current work is to examine the effect of thickness on fiberglass reinforced epoxy matrix subjected to high velocity impact loading. The composite material chosen for this research was from type C-glass/epoxy 200 g/m2 and type C-glass/epoxy 600 g/m2. This material is used as a composite reinforcement in high performance applications since it provides certain advantages of specific high strength and stiffness as compared to metallic materials. This study investigates the mechanical properties, damage characterisation and impact resistance of both composite structures, subjected to the changes of impact velocity and thickness. For mechanical properties testing, the Universal Testing Machine (UTM) was used while for the high velocity impact, a compressed gas gun equipped with a velocity measurement system was used. From the results, it is found that the mechanical properties, damage characterisation and impact resistance of type C-glass/Epoxy 600 g/m2 posses better toughness, modulus and penetration compared to type C-glass/Epoxy 200 g/m2. A general trend was observed on the overall ballistic test results which indicated that as the plate specimen thickness continues to increase, the damage at the lower skin decreases and could not be seen. Moreover, it is also found that, as the plate thickness increases, the maximum impact load and impact energy increases relatively. Impact damage was found to be in the form of perforation, fibre breakage and matrix cracking. Results from this research can be used as a reference in designing structural and body armour applications in developing a better understanding of test methods used to characterise impact behaviour.

Condition Structural Index using Principal Component Analysis for undamaged, damage and repair conditions of carbon fiber–reinforced plastic laminate

This article deals with the data reduction technique using the principal component analysis applied to the carbon fiber–reinforced plastic panels for structural health monitoring approaches. Two carbon fiber–reinforced plastic panels subjected to damage and repair coincide with typical aircraft repair procedures found in the aircraft structural repair manual. The panels were simulated with 30 mm diameter of partial and full penetration damages using a diamond-coated router. The data (50 observations) were captured for the undamaged, damaged, and repaired conditions by placing lead zirconate titanate smart sensors at 100 mm across the damaged and repaired structures. A time-based data response was captured for post analysis during the interrogation on the structure at each condition. The raw data were captured in a Lamb waveform, and the interested features were extracted using Morlet wavelet analysis to evaluate the Condition Structural Index and Amplitude-Based Assessment for each condition retrieved from the Gaussian-like distribution. The results were evaluated using the principal component analysis technique in order to distinguish the characteristic of the undamaged, damaged, and repaired conditions. The results showed that in all cases considered, it was possible to distinguish the conditions of undamaged, damaged, and repaired states with promising accuracy and repeatability of the data.

Thermal Free Vibration Analysis of Temperature-Dependent Functionally Graded Plates Using Second Order Shear Deformation

This research has been conducted to approach second-order shear deformation theory (SSDT) to analysis vibration characteristics of Functionally Graded Plates (FGP’s). Material properties in FGPs were assumed to be temperature dependent and graded along the thickness using a simple power law distribution in term of the volume fractions of the constituents. FGP was subjected to a linear and nonlinear temperature rise. The energy method was chosen to derive the equilibrium equations. The solution was based on the Fourier series that satisfy the simply supported boundary condition (Naviers method). Numerical results indicated the effect of material composition, plate geometry, and temperature fields on the vibration characteristics and mode shapes. The results revealed that, the temperature field and volume fraction distribution had significant effect on the vibration of FGPs. It was observed the second order theory was very close to the other shear deformation theorem as reported in the literature.

Tensile Properties of Woven Carbon/Kevlar Reinforced Epoxy Hybrid Composite

Carbon fibres and Kevlar fibres are among the commonly used fibres in the composite industry. As carbon fibres usually known for its superior strength, its low impact resistance limited its application in the industry. However, further research found that combining the high strength fibres with more ductile fibres like Kevlar could improve the material’s impact resistance. This hybrid effect was also found to be most effective by using intra-ply woven hybrid fibres in the composite. In this work, hybrid composite material was fabricated by using woven carbon-Kevlar cloths with epoxy matrix and the mechanical properties are determined at 0 ̊, 45 ̊ and 90 ̊. The hybrid composite material was found to have highest tensile strength at 0 ̊ (carbon) direction. As the material’s strength and tensile behaviour are different at every fibre types, the selection of fibre direction of the woven cloth in loading is an important criteria in any applications.

A Brief Research Review for Improvement Methods the Wettability between Ceramic Reinforcement Particulate and Aluminium Matrix Composites

The development of new methods for addition fine ceramic powders to Al aluminium alloy melts, which would lead to more uniform distribution and effective incorporation of the reinforcement particles into the aluminium matrix alloy. Recently the materials engineering research has moved to composite materials from monolithic, adapting to the global need for lightweight, low cost, quality, and high performance advanced materials. Among the different methods, stir casting is one of the simplest ways of making aluminium matrix composites. However, it suffers from poor distribution and combination of the reinforcement ceramic particles in the metal matrix. These problems become significantly effect to reduce reinforcement size, more agglomeration and tendency with less wettability for the ceramic particles in the melt process. Many researchers have carried out different studies on the wettability between the metal matrix and dispersion phase, which includes added wettability agents, fluxes, preheating the reinforcement particles, coating the reinforcement particles, and use composting techniques. The enhancement of wettability of ceramic particles by the molten matrix alloy and the reinforcement particles distribution improvement in the solidified matrix is the main objective for many studies that will be discussed in this paper.

Quasi Static Analysis of a Biocomposite Aircraft Radome

This paper investigates the quasi static compression analysis behavior of a biocomposite radome using nonlinear static modeling. Bio-based fiber is proposed to be used in aircraft radome due to its low dielectric constant. In this instance, kenaf was being utilized as the natural fiber to form a hybrid combination of fiberglass/kenaf epoxy laminates. The quasi static behavior was modeled using MDNastran SOL106 Nonlinear Static. The radome was modeled as a hemispherical shell based on Beechcraft’s radome geometric configuration. The radome is designed as a four-layered laminates with randomly oriented fiberglass and kenaf. The nonlinear compression was performed in the range of 0.01 mm to 0.49 mm with a maximum reaction force of 189 N. The radome was not displaced equally or symmetrically as the translational load applied since the shape of radome is asymmetry and the surface at the top is uneven. The increment of the forces leads to elastic local flattening deformation at the apex of the radome. Its shape influences in determining the displacement and the stress to the radome.

A Structural Health Monitoring of a Pitch Catch Active Sensing of PZT Sensors on CFRP Panels: A Preliminary Approach

© 2012 Aris et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A Structural Health Monitoring of a Pitch Catch Active Sensing of PZT Sensors on CFRP Panels: A Preliminary Approach

Modal Properties of a Cantilevered Laminated Woven Composite Plate as Affected by Stacking Sequence and Fiber Orientation: An Experimental Study

The use of laminated composites in aircraft structures is not totally new. However, the idea of using woven fiber glass as reinforcement in primary structural members is not widely addressed as compared to unidirectional fibers. In an effort to characterize the dynamic behavior of a woven laminated composite subject to dynamic loads, modal testing is performed experimentally on a cantilevered laminated woven glass fiber/epoxy composite flat plate which resembles an aircraft wing with aspect ratio of 5. To that end, the effect of stacking sequence and fiber orientation of the laminated composite plate on the modal properties is assessed. 6-layer laminated composite configurations with various stacking sequence and fiber orientation are fabricated so as to generate variable stiffness plates. The modal test employs the single roving hammer technique to obtain the frequency response of the plate and the results of the first five modes against the fiber orientation and stacking sequence are analyzed.