Abstract
This paper presents a comprehensive review of the current state of knowledge of second harmonic generation (SHG) measurements, a subset of nonlinear ultrasonic nondestructive evaluation techniques. These SHG techniques exploit the material nonlinearity of metals in order to measure the acoustic nonlinearity parameter, $$\beta $$β. In these measurements, a second harmonic wave is generated from a propagating monochromatic elastic wave, due to the anharmonicity of the crystal lattice, as well as the presence of microstructural features such as dislocations and precipitates. This article provides a summary of models that relate the different microstructural contributions to $$\beta $$β, and provides details of the different SHG measurement and analysis techniques available, focusing on longitudinal and Rayleigh wave methods. The main focus of this paper is a critical review of the literature that utilizes these SHG methods for the nondestructive evaluation of plasticity, fatigue, thermal aging, creep, and radiation damage in metals.
Original language | English (US) |
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Journal | Journal of Nondestructive Evaluation |
Volume | 34 |
Issue number | 1 |
DOIs | |
State | Published - Mar 1 2015 |
Externally published | Yes |
Keywords
- Microstructural evolution in metal
- Nonlinear ultrasonic measurements
- Second harmonic generation
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering