Acoustic Emission

1 Macrofracture of Structural Materials and Methods

of Determining its Type................................................................................................... 1

1.1      Types of Structural Materials Fracture................................................................ 1

1.2      Application of the Acoustic Emission Method to Detect

the Fracture of Structural Materials...................................................................... 8

1.3      Detection of Defects by Signals

of Magnetoelastic Acoustic Emission ................................................................ 19

1.4      Methods of Spectral Analysis of AE Signals................................................... 21

1.5      Application of Wavelet Transform for

Analysis of AE signals........................................................................................... 31

References............................................................................................................................... 43

2 Mathematical Models for Displacement Fields Caused by

the Crack in an Elastic Half-Space............................................................................ 61

2.1      Basic Relations of Three-Dimensional Dynamic Problems

of the Theory of Elasticity for Bodies with Cracks........................................... 62

2.2      Modeling of Wave Displacements Field on the Half-Space

Surface due to Displacement of the Internal Crack Faces............................... 68

References............................................................................................................................ 102

3 Energy Criterion for Identification of the Types of

Material Macrofracture............................................................................................. 105

3.1      Methods for Identifying the Types of Macrofracture................................... 105

3.2      Construction of the Energy Criterion.............................................................. 108

3.3      Continuous Wavelet Transform of the AE Signals Emitted

under Fracture of Aluminum and its Alloy...................................................... 123

3.4    Specific Features of the Acoustic Emission Signals During Fracture of Aluminum Alloy Welded Joints under

Quasi-Static Loading............................................................................................ 130

3.5      AE-identification of the Types of Fracture during

Low-Temperature Creep Crack Growth........................................................... 135

3.6      Application of the Wavelet Transform to Study the

Features of Non-Metallic Materials Fracture................................................... 140

References............................................................................................................................ 144

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4 Evaluation of the Types and Mechanisms of Fracture

of Composite Materials According to Energy Criteria...................................... 151

4.1      Specific Features of Macrofracture of the Glass

Fiber Reinforced Composites............................................................................ 152

4.2      AE-diagnostics of Fracture of the Aramid

Fiber Reinforced Composites............................................................................ 159

References............................................................................................................................ 179

5 Ranking of Dental Materials and Orthopedic Constructions

by their Tendency to Fracture.................................................................................. 185

5.1      State-of-the Art of Researches on Mechanical Properties

of Dental Materials............................................................................................. 186

5.2      Determination of the Characteristics of Materials for Temporary

Fixed Constructions of Dentures...................................................................... 187

5.3      Evaluation of the Types of Dental Polymer Fracture by

the Energy Criterion........................................................................................... 199

5.4      Peculiarities of Some Tooth-Endocrown

Systems Fracture under Quasi-Static Loading............................................... 205

References............................................................................................................................ 220

6 Rating of Hydrogen Damaging of Steels by Wavelet

Transform of Magnetoelastic Acoustic Emission Signals................................. 227

6.1      Some Aspects of Operation the Technical Systems

in Hydrogenous Medium................................................................................... 228

6.2      Method for Estimating the Hydrogen Damage of Structural

Materials by Wavelet Transform of MAE Signals........................................ 232

6.3      Approbation of the Research Technigue on Specimens of

Long-Term Operated Pipe Steels..................................................................... 244

References............................................................................................................................ 255