Laser Generation and Interferometric Detection of Ultrasound in Anisotropic Materials
Current investigation into the influences of material anisotropy on the signature of laser generated waveforms in single crystals using interferometric detection has shown that the orientation of the lattice not only influences the speed of wave propagation but also the overall shape of the detected waveform. In few grained crystalline materials which exhibit strong anisotropy, the misorientation of grains relative to one another may be observed in the signature of detected waveforms. As a result of the reproducibility and the inherent directivity of laser generated ultrasound, the lattice orientation of a specimen relative to its boundaries may be inferred by observing both wave velocities and wave signatures.
KeywordsMaterial Anisotropy Line Source Laser Generation Lattice Orientation Order Elastic Constant
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