Measurement of Nonlinear Ultrasonic Characteristics

Kyung-Young Jhang received his PhD from Tokyo Institute of Technology, Japan in 1991. He is currently a Professor and the Chair of Mechanical Engineering at Hanyang University. His research focuses on the area of linear & nonlinear ultrasonics for NDT&E, laser ultrasonics and laser-material intraction, ultrasonic and optical measurements and signal & image processing. He was Vice-president of Korean Society for NDT and Editor-in-Chief of Journal of the Korean Society for NDT (2012-2017).

• Preface.- Chapter 1. Overviews: Nonlinear Ultrasonic Characteristics and Measurands.- Chapter 2. Elastic Nonlinearity induced Nonlinear Ultrasonic Characteristics.- 2.1 Higher Harmonics (HH) Generation,-2.2 Nonlinear Ultrasonic Parameters.- 2.2.1 Absolute Nonlinear Ultrasonic Parameter.- 2.2.2 Relative Nonlinear Ultrasonic Parameter.- 2.3 Measurement of Nonlinear Ultrasonic Parameter.- 2.3.1 Capacitive Detection and Laser-interferometric Detection.- 2.3.2 Piezo-electric Detection.- 2.3.3 Control of Propagation Distance and Control of Incident Wave Power.- 2.3.4 Phase Inversion Technique.- 2.4 Factors Affecting to Measurement Reliability.- 2.4.1 Measurement System: Transducer, Input Power, Contact Pressure, Electronic Equipment.- 2.4.2 Digital Signal Processings: Bandwidth of Incident Wave, Time Resolution, Amplitude Resolution.- 2.5 Applications to Assessment of Material Damage.- 2.5.1 Fatigue Damage.- 2.5.2 Plastic Deformation.- 2.5.3 Thermal Aging.- References.- Chapter 3. Nonlinear Acoustic Wave Interactions with Contact Interfaces: Methodologies and Applications.- 3.1. Nonlinear Reflection Approach to Interface Nonlinearity.- 3.1.1 Nonlinear acoustic reflection at an ideally bonded interface.- 3.2.1 Application of Reflection Concept to Nonlinear Interface Wave Propagation.- 3.3.1 Second Harmonic Generation of Interface Acoustic Waves.- 3.2. Acoustic Nonlinearity of a Non-Bonded Interface.- 3.2.1  Phenomenology of Contact Acoustic Nonlinearity (CAN).- 3.2.2  Higher Harmonics (HH) Generation at Contact Interfaces.- 3.2.3  Nonlinear Acoustic Reflection by Fractured Defects.- 3.2.4  Acoustic Rectification and Nonlinear Polarization Effects via CAN.- 3.3. Non-Classical Nonlinear Effects in Resonant Contact Inclusions.- 3.3.1  Concept of Local Defect Resonance.- 3.3.2  Sub- and Super-harmonic Resonances.- 3.3.3  Nonlinear Parametric Instability Effects.- 3.4. Applications for NonlinearImaging of Defects.- 3.4.1  Nonlinear Scanning Laser Vibrometry.- 3.4.2  Nonlinear Air-Coupled Emission (NACE).- 3.4.3  Case Studies of Nonlinear Imaging of Defects.- References.- Chapter 4. Nonlinear Ultrasonic Phased Array for Measurement of Closed-Crack Depth.- 4.1. Introduction.- 4.2. Harmonics.- 4.2.1. Principles.- 4.2.2. Experimental conditions.- 4.2.3. Imaging results.- 4.3. Parallel and sequential transmission.- 4.3.1. Principles.- 4.3.2. Experimental conditions.- 4.3.3. Imaging results.- 4.4. Full-, odd- and even-elements transmission.- 4.4.1. Principles.- 4.4.2. Experimental conditions.- 4.4.3. Imaging results.- 4.5. Utilization of thermal stress.- 4.5.1. Principles.- 4.5.2. Experimental conditions.- 4.5.3. Imaging results.- References.- Chapter 5. Nonlinear Guided Waves.- 5.1. Introduction.- 5.2. Background on guided wave propagation.- 5.3. Self Interaction.- 5.3.1. Basic principles.- 5.3.2. Lamb waves in plate.- 5.3.3. Shear horizontal waves in plate.- 5.3.4. Axisymmetric waves in pipe.- 5.3.5. Flexural waves in pipe.- 5.4. Mutual interaction in plate.- 5.4.1. Basic principles.- 5.4.2. Collinear waves.- 5.4.3. Non-collinear waves.- 5.5. Actuation of primary waves and reception of secondary waves.- 5.5.1. Actuation of Lamb and L(0,n) waves.- 5.5.2. Actuation of SH and T(0,n) waves.- 5.5.3. Reception.- 5.5.4. Effects of diffraction .- 5.6. Signal processing.- 5.6.1. Fast Fourier transform.- 5.6.2. Phase inversion.- 5.7. Measurement considerations.- 5.7.1. Measurement nonlinearities.- 5.7.2. Material nonlinearity.- 5.7.3. Contact acoustic nonlinearity.- 5.7.4. Measuring progressive degradation.- References.- Chapter 6. Nonlinear Frequency-Mixing Photoacoustic Characterization of a Crack .- 6.1. Introduction in nonlinear photoacoustics.- 6.1.1. An overview of NDT methods combining laser optics with nonlinear acoustics.- 6.1.2.Generation of the thermo-elastic stresses and of acoustic waves by modulation of cw-laser radiation.- 6.1.3. Influence of stationary laser heating on a crack.- 6.2. Nonlinear frequency-mixing photo-acoustic method for crack detection.- 6.2.1. Principle of the method.- 6.2.2. One dimensional imaging of a crack.- 6.2.3. Two-dimensional imaging of a crack.- 6.2.4. Role of classical and nonclassical nonlinearities.- 6.3. Breathing and spatial resolution evolution with experimental parameters.- 6.3.1. Influence of the probe power.- 6.3.2. Influence of the pump power.- 6.3.3. Influence of the local crack parameters.- 6.4. Towards quantitative evaluation of local crack parameters.- 6.4.1. Experimental observations.- 6.4.2. Theoretical model,-6.4.3. Extraction of crack parameters,-References