Download or read book Damage Detection of Carbon Fiber Reinforced Polymer Using Electrical Measurement and Analysis of Acoustic Emission Signals written by Heng-Hsueh Chen and published by . This book was released on 2013 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon fiber reinforced polymer composites (CFRPs) have been widely used in aerospace, civil engineering and so on in recent decades because of their excellent mechanical properties (high strength and stiffness), low density, long-term durability and high resistances to corrosion, pressure and other harsh environment conditions. Since CFRPs are multiphase materials that consist of polymer matrix and carbon fibers plies. Local separation between plies and/or debonding at fiber-matrix interface may occur during application. Damage in this form of delamination may affect the material properties such as the ability of stress transmission, which leads to component failure in the vehicles or even disastrous loss. Hence, the study of damage detection is necessary to ensure the safety use of CFRPs. In this thesis, we first introduce the tensile test for CFRP sample. The test is conducted by hydraulic wedge grip with electrical potential measurement and acoustic emission sensors, respectively. Continuous wavelet transform is applied to analyze output signals, which enables us to see the differences between unbroken and broken samples. Electrical potential measurement provides direct information from the original output signal about the sample damage, and there is no external sensors needed. Acoustic emission method, on the other hand, helps us to make hypothesis on recognizing different failure modes. Then we study the impact of damage in the form of delamiantion and the damage in the form of hole. By measuring the electrical potential, we estimate the damage location experimentally, and the linear relationship between damage dimension ratio and average/maximum ratio of potential change is developed to estimate the damage size. Then via 3D FEA modeling, we study the undamaged and damaged cases numerically with the same conditions as in the experimental study, and the electrical potential distributions are obtained to evaluate the damage. The numerical result shows good agreement with the experimental result.

Download or read book Non destructive Testing of Impact Damage in Fiber reinforced Polymer Composites written by Milad Saeedifar and published by Elsevier. This book was released on 2024-08-08 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-destructive Testing of Impact Damage in Fiber-reinforced Polymer Composites: Fundamentals and Applications provides detailed knowledge on the fundamentals and applications of frequently used nondestructive testing (NDT) techniques utilized to assess impact damage in composite structures. This book starts with an introduction to impact damage in composite structures, each subsequent chapter focuses on evaluating damage using specific NDT methods. Chapters 2–4 concentrate on vision-based NDT methods such as visual inspection, digital image correlation, and digital shearography. Following this, Chapters 5–6 delve into ultrasound-based methods, including acoustic emission and phased-array ultrasonic inspection. Radiation-based methods, micro-CT, and thermography are discussed in Chapters 7 and 8, while Chapters 9 and 10 elucidate microwave inspection and electrical impedance tomography. This book is a useful reference for both academia and industry and covers the fundamentals, practical tips, case studies, and applications, as well as current research trends and future possibilities, for each technique. - Insights into the diverse damage levels in composite materials resulting from low-velocity impact, ranging from micro matrix cracks to severe delamination and fiber breakage - Covers a broad range of NDT techniques, including recently developed NDT techniques, suitable for detecting impact damage in composite materials - Serves as a valuable reference for both academia and industry, providing comprehensive coverage of fundamental principles, practical insights, applications, case studies, current research trends, and future prospects for each NDT technique

Download or read book Coupled Electrical and Thermal Damage Detection in Carbon Fiber Reinforced Polymers written by Jie Wen and published by . This book was released on 2011 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon fiber reinforced polymer matrix composites (CFRPs) are widely applicable in various important structural components for aircraft, spacecraft, civil structures and energy generation infrastructures. One of the critical issues in the successful application of CFRPs is nondestructive assessment of damage state in a particular structural component. Electrical measurement is an emerging non-destructive evaluation technology for real-time/on-board damage detection in CFRPs. In this research, electrical potential was measured in an efficient A/D & D/A system to detect the damage in the CFRPs. There were three types of signals generated, DC, Sine wave, and the wavelet signal. To solve the problem of noise influence in the experiment, the wavelet theory has been demonstrated as a remarkable tool for noise reduction by comparing to the traditional signal analysis methods. Another part of this research is the coupled thermal-electrical analysis. To conduct the thermal study, the DC signal was employed to the CFRP sample as a thermal heating source for both experimental and numerical studies. In experimental study, the change of differential electrical potential was investigated to locate the damage and ratios of potential change were used to correlate with the damage size. Two linear relations were developed to evaluate the damage size, the variables of maximum ratio and average ratio of the potential changes. The thermal response was studied with thermography tests and results are compared to indicate the damage on the CFRP using temperature distribution changes. When the temperature distributions were compared to those of the electrical measurements, they were in good agreement in locating the damage. In the numerical analysis, the 3D coupled thermal-electrical finite element models have been successfully generated to simulate the electrical potential and the nodal temperature distributions. The experimental results and the numerical results have shown good agreement with each other.

Download or read book American Society for Composites American Society for Testing And Materials Committee D30 written by Erian Armanios and published by DEStech Publications, Inc. This book was released on 2004-10 with total page 1464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Highlights the recent developments in the fundamental understanding of composites; important information for researchers and composite scientists.

Download or read book Proceedings of the Tenth International Conference on Composite Materials written by Anoush Poursartip and published by Woodhead Publishing. This book was released on 1995 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1988 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Detection and Localization of Damage in Fiber Reinforced Polymer Bars Using Acoustic Emission Detection Micro Computed Tomography and Scanning Electron Microscopy Techniques written by Maha Ghaib and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fiber reinforced polymer (FRP) rebars have been used for reinforcing concrete structures for the last quarter of the century. The advantages of using FRP are: high strength to weight ratio, corrosion resistance, durability, and high tensile strength. It would be beneficial to have non-destructive testing (NDT) methods that have the potential to detect damage at loads well below failure. This is particularly important for FRP rebars as they do not exhibit any external signs of damage until brittle failure. However, internal damage in FRP rebars increases with increasing tensile loads. Acoustic emission (AE) signal has proved to be a useful tool for monitoring damage in FRP materials. However, FRP rebars have received little attention. In this work damage progression in different types of FRP rebars subjected to tension was studied using AE, SEM and μCT. One possible mechanism for damage progression is the growth of voids entrapped in FRP rebars during their manufacture. These voids are a weakened region within the bars. When the bar is subjected to stress these regions can grow in size. In this work the growth of the voids within the bar is interpreted as the progression of damage. Internal voids and their growth were observed using micro computed tomography (μCT) and scanning electron microscopy (SEM) and compared to AE results. Strong correlation was observed between the void volume growth determined using μCT analysis and cumulative energy of AE. This work also demonstrated improved methods used to locate the source of AE signals that occurred in FRP rebars subjected to tension. An artificial neural network (ANN) was used to reduce the uncertainty in determining the AE source location. The ANN had improved accuracy, compared to the conventional source location methods by factor of 1.6 and 3 for GFRP and CFRP samples respectively. The source location results obtained with the ANN were also compared to μCT void volume analysis along the length of the bars after tension testing.

Download or read book Damage Detection in Carbon Fiber Composites Using Electrical Resistance Measurements written by Ryan Steven Gory and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: This thesis proposes a methodology for structural health monitoring that incorporates the inherent multi-functionality of carbon fibers. The hypothesis of the thesis is that by monitoring the electrical resistance of composite panels it is possible to detect impacts and statistically model their effects on the remaining useful service life of structures. The proposed research investigates the application of statistics-based analysis to the measured electrical resistance signals during loading. The research also investigates the use of electrical resistance as a stress sensor by monitoring the resistance of test samples under tensile loading.

Download or read book Structural Health Monitoring Damage Detection Systems for Aerospace written by Markus G. R. Sause and published by Springer Nature. This book was released on 2021 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book presents established methods of structural health monitoring (SHM) and discusses their technological merit in the current aerospace environment. While the aerospace industry aims for weight reduction to improve fuel efficiency, reduce environmental impact, and to decrease maintenance time and operating costs, aircraft structures are often designed and built heavier than required in order to accommodate unpredictable failure. A way to overcome this approach is the use of SHM systems to detect the presence of defects. This book covers all major contemporary aerospace-relevant SHM methods, from the basics of each method to the various defect types that SHM is required to detect to discussion of signal processing developments alongside considerations of aerospace safety requirements. It will be of interest to professionals in industry and academic researchers alike, as well as engineering students. This article/publication is based upon work from COST Action CA18203 (ODIN - http://odin-cost.com/), supported by COST (European Cooperation in Science and Technology). COST (European Cooperation in Science and Technology) is a funding agency for research and innovation networks. Our Actions help connect research initiatives across Europe and enable scientists to grow their ideas by sharing them with their peers. This boosts their research, career and innovation.

Download or read book Damage Detection in Composite Materials Using Acoustic Emission and Self sensing Fibres written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of this study was to investigate the abilities of acoustic emission testing and self-sensing fibres to detect damage in composite materials. This was achieved by performing acoustic emission testing on fibre samples and resin samples during tensile tests. In parallel to the acoustic emission testing the changes in strain for the resin samples was recorded using electrical resistance strain gauges and fibre Bragg gratings. Acoustic emission testing of Self-sensing fibre composites allowed the recorded changes in the light intensity transmitted by the fibres to be analysed in conjunction with the acoustic emission data. The fabrication of the three different sample types is presented as is the installation of the electrical resistance strain gauges and fibre Bragg gratings. The experimental procedure and method of data capture is detailed for tensile and acoustic emission testing, strain data and Self-sensing fibre data. The fabrication and testing of the samples was performed successfully. The testing procedure and analysis of results demonstrates the accurate use of acoustic emission and the potential of self-sensing fibres in detecting damage in composite materials.

Download or read book Proceedings of the 2nd International Conference on Emerging Technologies and Intelligent Systems written by Mohammed A. Al-Sharafi and published by Springer Nature. This book was released on 2022-12-12 with total page 703 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book sheds light on the recent research directions in intelligent systems and their applications. It involves four main themes: artificial intelligence and data science, recent trends in software engineering, emerging technologies in education, and intelligent health informatics. The discussion of the most recent designs, advancements, and modifications of intelligent systems, as well as their applications, is a key component of the chapters contributed to the aforementioned subjects.

Download or read book Interface Interphase in Polymer Nanocomposites written by Anil N. Netravali and published by John Wiley & Sons. This book was released on 2016-11-29 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant research has been done in polymeric nanocomposites and progress has been made in understanding nanofiller-polymer interface and interphase and their relation to nanocomposite properties. However, the information is scattered in many different publication media. This is the first book that consolidates the current knowledge on understanding, characterization and tailoring interfacial interactions between nanofillers and polymers by bringing together leading researchers and experts in this field to present their cutting edge research. Eleven chapters authored by senior subject specialists cover topics including: Thermodynamic mechanisms governing nanofiller dispersion, engineering of interphase with nanofillers Role of interphase in governing the mechanical, electrical, thermal and other functional properties of nanocomposites, characterization and modelling of the interphase Effects of crystallization on the interface, chemical and physical techniques for surface modification of nanocellulose reinforcements Electro-micromechanical and nanoindentation techniques for interface evaluation, molecular dynamics (MD) simulations to quantify filler-matrix adhesion and nanocomposite mechanical properties.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 974 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Innovative Developments of Advanced Multifunctional Nanocomposites in Civil and Structural Engineering written by Kenneth Loh and published by Woodhead Publishing. This book was released on 2016-02-03 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: Innovative Developments of Advanced Multifunctional Nanocomposites in Civil and Structural Engineering focuses on nanotechnology, the innovation and control of materials at 100 nm or smaller length scales, and how they have revolutionized almost all of the various disciplines of science and engineering study. In particular, advances in synthesizing, imaging, and manipulating materials at the nano-scale have provided engineers with a broader array of materials and tools for creating high-performance devices. Nanomaterials possess drastically different properties than those of their bulk counterparts mainly because of their high surface-to-mass ratios and high surface energies/reactivity. For instance, carbon nanotubes have been shown to possess impressive mechanical strength, stiffness, and electrical conductivity superior to that of bulk carbon. Whilst nanotechnology has become deeply rooted in electrical, chemical, and materials engineering disciplines, its proliferation into civil engineering did not begin until fairly recently. This book covers that proliferation and the main challenges associated with the integration of nanomaterials and nano-scale design principles into civil and structural engineering. - Examines nanotechnology and its application to not only structural engineering, but also transportation, new infrastructure materials, and the applications of nanotechnology to existing structural systems - Focuses on how nanomaterials can provide enhanced sensing capabilities and mechanical reinforcement of the original structural material - Analyzes experimental and computational work carried out by world-renowned researchers

Download or read book Emerging Technologies in Non Destructive Testing V written by Alkiviadis S. Paipetis and published by CRC Press. This book was released on 2012-01-26 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-destructive evaluation (NDE) methods have dominated most of the fields of applied research and technology over the last twenty years. These techniques provide information on the functional efficiency of materials and structures without causing any structural impact on the structure itself. Their use enables the monitoring of the structural integrity, the structural condition as well as the service in-duced degradation of materials and structures during their service life. In this respect, they address a vast field of applications ranging from the aerospace and automotive industry to civil engineering structures and material quality control. This volume comprises scientific papers presented during the Fifth Conference on Emerging Technologies in Non-Destructive Testing (Ioannina, Greece, 19–21 September 2011). A broad spectrum of related research was presented during the course of the conference, including optical, acoustic, thermal, electrical and electromagnetic methods together with imaging tomographic and signal processing techniques. Special attention was given to NDE for Civil Engineering Structures and for the first time in the conference series, a multiple session on NDE for the protection of cultural heritage was organized. Emerging Technologies in Non-Destructive Testing V contains contributions by experts in this field from 22 different countries worldwide. Reflecting the stateof-the-art in Non-Destructive Evaluation, the book will prove to be a valuable companion to students, engineers and industrial partners who are active in the field of non-destructive evaluation and testing. This volume will also provide students and researchers with insight into the focal points of contemporary research efforts in the field of non-destructive evaluation.

Download or read book Acoustic Emission Testing written by Christian U. Grosse and published by Springer Science & Business Media. This book was released on 2008-07-12 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic Emission (AE) techniques have been studied in civil engineering for a long time. The techniques are recently going to be more and more applied to practical applications and to be standardized in the codes. This is because the increase of aging structures and disastrous damages due to recent earthquakes urgently demand for maintenance and retrofit of civil structures in service for example. It results in the need for the development of advanced and effective inspection techniques. Thus, AE techniques draw a great attention to diagnostic applications and in material testing. The book covers all levels from the description of AE basics for AE beginners (level of a student) to sophisticated AE algorithms and applications to real large-scale structures as well as the observation of the cracking process in laboratory specimen to study fracture processes.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt: