Chinese Optics Letters, 2008, 6 (11): 837, Published Online: Nov. 17, 2008
Investigation of surface acoustic waves in laser shock peened metals Download: 516次
激光 声表面波 冲击硬化 色散 140.0140 Lasers and laser optics 240.6690 Surface waves 280.3375 Laser induced ultrasonics 160.0160 Materials
Abstract
Laser shock peening is a well-known method for extending the fatigue life of metal components by introducing near-surface compressive residual stress. The surface acoustic waves (SAWs) are dispersive when the near-surface properties of materials are changed. So the near-surface properties (such as the thickness of hardened layers, elastic properties, residual stresses, etc.) can be analyzed by the phase velocity dispersion. To study the propagation of SAWs in metal samples after peening, a more reasonable experimental method of broadband excitation and reception is introduced. The ultrasonic signals are excited by laser and received by polyvinylindene fluoride (PVDF) transducer. The SAW signals in aluminum alloy materials with different impact times by laser shock peening are detected. Signal spectrum and phase velocity dispersion curves of SAWs are analyzed. Moreover, reasons for dispersion are discussed.
Ling Yuan, Gang Yan, Zhonghua Shen, Hangwei Xu, Xiaowu Ni, Jian Lu. Investigation of surface acoustic waves in laser shock peened metals[J]. Chinese Optics Letters, 2008, 6(11): 837.