Acoustic Emission: Fracture Detection in Structural Materials

Preface
Contents
Abbreviations
1 Macrofracture of Structural Materials and Methods of Determining Its Type
	1.1 Types of Structural Materials Fracture
		1.1.1 Ductile Fracture
		1.1.2 Brittle Fracture
		1.1.3 Mixed-Mode (Ductile–Brittle or Brittle–Ductile) Fracture
	1.2 Application of the Acoustic Emission Method to Detect the Fracture of Structural Materials
		1.2.1 General Information About Acoustic Emission
		1.2.2 Some Approaches to the Identification of Fracture Types by the AE Method
		1.2.3 Identification of Fracture Mechanisms of Composite Materials
	1.3 Detection of Defects by Signals of Magnetoelastic Acoustic Emission
	1.4 Methods of Spectral Analysis of AE Signals
		1.4.1 Continuous Wavelet Transform
		1.4.2 Discrete Wavelet Transform
	1.5 Application of Wavelet Transform for Analysis of AE Signals
		1.5.1 Wavelet Analysis of AE Signals in the Course of TD
		1.5.2 WT in the Problems of AE Sources Location and Identification of Defects in Structural Materials
		1.5.3 Identification of the Mechanisms of Composites Fracture by Using the WT of AE Signals
		1.5.4 Wavelet Analysis in the MAE Signals Processing
		1.5.5 Application of the κ-Criterion for the Evaluation of the Fracture Types of Structural Materials
	References
2 Mathematical Models for Displacement Fields Caused by the Crack in an Elastic Half-Space
	2.1 Basic Relations of Three-Dimensional Dynamic Problems of the Theory of Elasticity for Bodies with Cracks
	2.2 Modeling of Wave Displacements Field on the Half-Space Surface Due the Displacement of the Internal Crack Faces
	References
3 Energy Criterion for Identification of the Types of Material Macrofracture
	3.1 Methods for Identifying the Types of Macrofracture
	3.2 Construction of the Energy Criterion
		3.2.1 Analysis of Fracture Types for Carbon Steel
		3.2.2 Specific Features of Alloyed Steel Fracture
		3.2.3 Specific Features of Brittle Materials Fracture
	3.3 Continuous Wavelet Transform of the AE Signals Emitted Under Fracture of Aluminum and Its Alloy
		3.3.1 Investigation of the Aluminum Fracture by Parameters of the CWT of AE Signals
		3.3.2 Analysis of AE Signals During Fatigue Fracture of Aluminum Alloy
	3.4 Specific Features of the Acoustic Emission Signals During Fracture of Aluminum Alloy Welded Joints Under Quasi-Static Loading
		3.4.1 Identification of Fracture Sources of Different Zones of Aluminum Alloy Welded Joints by Fractographic Analysis of the Fracture Surfaces
		3.4.2 Peculiarities of AE Signals During Fracture of the 1201-T Alloy Welded Joint
	3.5 AE-Identification of the Types of Fracture During Low-Temperature Creep Crack Growth
	3.6 Application of the Wavelet Transform to Study the Features of Nonmetallic Materials Fracture
	References
4 Evaluation of the Types and Mechanisms of Fracture of Composite Materials According to Energy Criteria
	4.1 Specific Features of Macrofracture of the Glass Fiber-Reinforced Composites
		4.1.1 Substantiation of the Research Technique
		4.1.2 Results and Discussion
	4.2 AE-Diagnostics of Fracture of the Aramid Fiber-Reinforced Composites
		4.2.1 General Characteristic of the Aramid Fibers
		4.2.2 Influence of Various Factors on the Mechanical Properties of CM Reinforced with the Aramid Fibers
		4.2.3 Mechanisms of Unidirectional CM Fracture
		4.2.4 Substantiation of the Research Methods
		4.2.5 Results and Discussion
		4.2.6 Analysis of AE Signals During Tension of the Composite of Type 1
		4.2.7 Peculiarities of AE Signals During Tension of the Composite of Type 2
		4.2.8 Characteristics of AE Signals During Tension of the Composite of Type 3
		4.2.9 Parameters of AE Signals During Tension of the Composite of Type 4
	References
5 Ranking of Dental Materials and Orthopedic Constructions by Their Tendency to Fracture
	5.1 State of the Art of Researches on Mechanical Properties of Dental Materials
	5.2 Determination of the Characteristics of Materials for Temporary Fixed Constructions of Dentures
		5.2.1 Materials for Investigations
		5.2.2 Evaluation of Strength Characteristics of Polymers
		5.2.3 Evaluation of Water Absorption of Polymer Materials
		5.2.4 Determination of a Shrinkage
		5.2.5 Microhardness of Polymers
	5.3 Evaluation of the Types of Dental Polymer Fracture by the Energy Criterion
		5.3.1 Analysis of AE Under Tensile Fracture of Polymers
	5.4 Peculiarities of Some Tooth-Endocrown Systems Fracture Under Quasi-Static Loading
		5.4.1 Preparation of the Samples
		5.4.2 The Initiation of Fracture in the Fixed Orthopedic Tooth-Endocrown Restorations
		5.4.3 Specific Features of AE Signals Under Fracture of the Tooth-Endocrown Restorations. Analysis of AE Signals During Tooth Fracture
		5.4.4 Evaluation of AE Signals Under Fracture of the Samples Made of Different Materials
		5.4.5 Analysis of AE Signals During Fracture of the Tooth-Endocrown Restorations
	References
6 Rating of Hydrogen Damaging of Steels by the Wavelet Transform of Magnetoelastic Acoustic Emission Signals
	6.1 Some Aspects of Operation of the Technical Systems in Hydrogenous Medium
		6.1.1 Peculiarities of Oil and Gas Pipelines Operation
		6.1.2 Specific Features of Operation of Feed Water Pipelines in High-Pressure Power Units
		6.1.3 Mechanism of Hydrogenation of the FWP Metal
	6.2 Method for Estimating the Hydrogen Damage of Structural Materials by Wavelet Transform of Magnetoelastic AE Signals
		6.2.1 Theoretical Bases of the MAE Signals Analysis by WT
		6.2.2 Materials for Experimental Research
		6.2.3 The Procedure of Experimental Research
		6.2.4 The Results of Studies of MAE Signals During Remagnetizing of Hot-Rolled Carbon Steel Specimens
		6.2.5 The Results of Investigation of MAE Signals During Remagnetizing of High-Quality Low-Carbon Steel Specimens
	6.3 Approbation of the Research Technique on Specimens of Long-Term Operated Pipe Steels
		6.3.1 The Pipe of the Main Oil Pipeline
		6.3.2 Main Gas Pipeline
		6.3.3 A Pipe for Feed Water of UHP Power Unit
	References