Nondestructive Testing and Evaluation of Fiber-Reinforced Composite Structures

Foreword
Preface
Contents
1 Introduction and Background of Fiber-Reinforced Composite Materials
	1.1 Introduction and Synopsis
	1.2 Basics of Composites Materials
	1.3 Polymeric Matrices and Polymerization Processes
		1.3.1 Thermosets
		1.3.2 Thermoplastics
	1.4 Reinforcements for Polymer Matrix Composites
	1.5 Types of Fiber-Based Reinforcement Architectures
		1.5.1 Woven Fabric Architectures
		1.5.2 Preimpregnated Thermosets
		1.5.3 Non-crimp Fabric Architectures
	1.6 Types of Fibers Reinforcements
		1.6.1 Glass Fibers
		1.6.2 Carbon Fibers
		1.6.3 Aramid Fibers
		1.6.4 Boron Fibers
		1.6.5 Polyethylene Fibers
		1.6.6 Ceramic Fibers and Whiskers
		1.6.7 Natural Fibers
	1.7 Design of Polymer-Matrix Composites
	1.8 Polymer-Matrix Composites Manufacturing Procedures
		1.8.1 Hand or Manual Lay-Up Process
		1.8.2 Filament Winding
		1.8.3 Pultrusion
		1.8.4 Resin Transfer Molding
		1.8.5 Resin Film Infusion
		1.8.6 Resin Liquid Infusion
	1.9 Fiber Metal Laminates
	1.10 Sandwich Structures
	1.11 Properties of Fiber-Reinforced Composites
	1.12 Main Types of Deficiency in Polymer-Matrix Composites
		1.12.1 Material Processing Defects
		1.12.2 Manufacturing Defects
		1.12.3 In-Service Damage and Material Degradation
	1.13 Trends Towards Novel Technologies
	1.14 General Conclusions
	References
2 Introduction to Nondestructive Testing and Evaluation of Fiber-Reinforced Composites
	2.1 Approaching the Nondestructive Testing World
	2.2 Classification of Flaws Vis-À-Vis the NDT Techniques
	2.3 General Hints on Testing Techniques and Procedures
	2.4 Classification of NDT Techniques
	2.5 Inspection Requirements for NDT Techniques
	2.6 Regulations, Standards, and Recommended Practices for NDT
	2.7 Role of Research and Development in NDT
	2.8 Application of NDT: Impact of Globalization and Operator’s Perspectives
		2.8.1 Important Events in Academic and Industrial NDT
		2.8.2 Important Historical Dates in Standards Development
		2.8.3 Qualification and Certification of Personnel for NDT
	2.9 The Need for Reliability and Accurate Statistic Evaluation
	2.10 Probability of Detection in DNT
	2.11 Conclusions
	References
3 Visual Testing for Fiber-Reinforced Composite Materials
	3.1 Introduction
	3.2 Important Dates and Development
	3.3 Theory and Principles
		3.3.1 The Object Factors
		3.3.2 The Light and Test Structure Lighting
		3.3.3 The Human Factors
	3.4 Visual Inspection Requirements
	3.5 Test Equipment and Accessories
		3.5.1 The Direct Visual-Eyes
		3.5.2 The Direct Visual Aids
		3.5.3 Remote Visual Testing
		3.5.4 Image Recording and Devices
		3.5.5 Image and Video Display Units
		3.5.6 Imaging Software and Digital Cameras
	3.6 Applications to the Inspection of Composite Structures
	3.7 Evaluation and Reporting of Visual Test Results
	3.8 Advantages and Limitations of Visual Testing
	3.9 Standards, Codes, and Specifications
	3.10 Conclusions
	References
4 Ultrasonic Testing Techniques for Nondestructive Evaluation of Fiber-Reinforced Composite Structures
	4.1 Introduction
	4.2 Operation and Variants of Ultrasonic NDT
	4.3 Types of Ultrasonic Waves
		4.3.1 Longitudinal Waves
		4.3.2 Shear Waves
		4.3.3 Rayleigh Waves
		4.3.4 Lamb Waves
	4.4 Types of Ultrasonic Transducers
	4.5 Ultrasound Generation and Coupling with the Composite
	4.6 Ultrasonic NDT Instruments for Composites
	4.7 Ultrasonic NDT Methods for Composite Structures
	4.8 Applications of Ultrasonic Inspection of Composite Laminates
	4.9 Ultrasonic Inspection of Sandwich Structures
		4.9.1 Through-Transmission Ultrasonic NDT
		4.9.2 Air-Coupled Ultrasonic Inspection of Sandwich Structures
		4.9.3 Inspection of Composite Sandwich with Perforated Facesheet
		4.9.4 In-Field Inspection of Honeycomb Sandwich Structures
	4.10 Performance Comparison of Ultrasonic NDT
	4.11 Current Trends and Prospects of Ultrasonic NDT
		4.11.1 Sizing of Flaws Using Ultrasonic NDT
		4.11.2 Signal Processing Techniques
		4.11.3 Standards for Composite Structures
		4.11.4 Integrated Inspection Systems
	4.12 Advantages and Limitations of Ultrasonic NDT
	4.13 Conclusions
	References
5 Infrared Thermography Testing and Evaluation of Fiber-Reinforced Composite Materials
	5.1 Introduction and History of IRT
	5.2 Generalities and Basic Concepts of IRT
		5.2.1 Passive Thermography
		5.2.2 Active Thermography
		5.2.3 Classification and Factors Determining Classes of Active IRT
	5.3 Thermal Properties of Materials
		5.3.1 Thermal Conductivity
		5.3.2 Thermal Diffusivity
		5.3.3 Thermal Effusivity
	5.4 Infrared Measuring Devices
	5.5 Emissivity and Reflected Temperature Measurement
	5.6 Established IR Thermographic NDT Techniques
		5.6.1 Optical Thermography
		5.6.2 Laser Thermography
		5.6.3 Eddy Current Thermography
		5.6.4 Microwave Thermography
		5.6.5 Vibrothermography and Ultrasound Thermography
	5.7 Scanning IR Thermographic NDT
		5.7.1 Line Scanning Thermography
		5.7.2 Scanning Eddy Current Thermography
	5.8 Applications of IRT-NDT for Composite Structures
	5.9 Performance Comparison of IRT and Other NDT Techniques
		5.9.1 Different Heating Functions
		5.9.2 Different Excitation Sources
		5.9.3 Comparison with Other NDTs
	5.10 Current Trends and IRT Research Prospects
		5.10.1 New Physics and Multiple Physics
		5.10.2 Signal Processing Techniques
		5.10.3 Integrated Inspection System
		5.10.4 Standards for Composites
	5.11 Advantages and Limitations of Using IRT
	5.12 Conclusions
	References
6 Terahertz Testing Technique for Fiber-Reinforced Composite Materials
	6.1 Introduction and Background Information
	6.2 Terahertz Devices and Systems
		6.2.1 Terahertz Pulsed Systems—THz-TDS
		6.2.2 Terahertz Continuous Wave Systems
	6.3 Imaging Theory and Procedures
	6.4 Applications of THz Systems to the Inspection of Fibrous Composites
		6.4.1 THz Imaging
		6.4.2 THz Spectroscopy
	6.5 Specific Application of THz Systems for the Evaluation of Composite Structures
		6.5.1 Online Process Monitoring
		6.5.2 Off-Line NDT Inspection
		6.5.3 Characterization of In-Service Damage and Material Degradation
	6.6 Outlook on Possible Future Applications of the THz Systems
	6.7 Conclusions
	References
7 Application of Acoustic Emission for the Inspection of Fiber-Reinforced Composite Materials
	7.1 Generalities
	7.2 Usage and History of AE
	7.3 Principle of Operation of an AE System
	7.4 AE Sensors Calibration and Coupling with Test Structure
	7.5 Sources of AE in Composite Materials
	7.6 Analysis Tools for AE Measurement Signals
		7.6.1 Distribution of Signal Hits in the Composite
		7.6.2 Source Localization of AE Signals in the Composite
		7.6.3 Identification of Wave Features
		7.6.4 Interpretation and Evaluation of AE Signals
	7.7 Applications in the Testing of Composite Structures
	7.8 Combination with Other NDE Techniques and Prospects
	7.9 Advantages and Limitations of AE Technique
	7.10 Current Trends and AE Standards
	7.11 Conclusions
	References
8 Other NDT Methods for Fiber-Reinforced Composite Structures
	8.1 Introduction
	8.2 Vibration Testing
	8.3 Strain Monitoring
	8.4 Electrical Testing
	8.5 Ground-Penetrating Radar, Microwave, and Millimeter Waves
		8.5.1 Ground-Penetrating Radar Inspection Technique
		8.5.2 Microwave Testing Technique (MW)
		8.5.3 Millimeter Waves (MmW) Testing Technique
	8.6 Optical Interferometric Techniques
	8.7 Radiography and Tomography
		8.7.1 Backscattered X-ray Imaging
		8.7.2 X-ray Computed Tomography Imaging
		8.7.3 Neutron Imaging Technique
		8.7.4 Nuclear Magnetic Resonance Imaging Technique
	8.8 Conclusions
	References
9 Conclusions, Current Developments, and Prospects in the NDT of Fiber-Reinforced Composites
	9.1 Conclusions
	9.2 Current Developments in the NDT of Fiber-Reinforced Composites
	9.3 Prospects in the NDT of Fiber-Reinforced Composites
	References