Deep Thermoacoustic Imaging Using Scanning Electron Acoustic Microscopy

Contrast Mechanisms in the Thermoacoustic Microscope

“…It is interesting to note that two recent experiments have Deen carried out using thermoacoustic microscopes with scatterer depths which were tens of thermal diffusion lengths from the source [13,14]. At these depths, the scattering certainly is acoustic.…”

“…At these depths, the scattering certainly is acoustic. In one of these experiments [13] the scatterer has a continuously varying aepth. In this experiment the observed resolution is two or three oraers of magnitude better than the acoustic wavelength and deteriorates linearly with depth, as predicted by the extreme-near-field theory [12].…”

Laser Thermomechanical Evaluation of Bonding Integrity

“…the moment becomes (4) Ic = bh3ft2 is the cross-sectional moment of inenia, and (5) Equilibrium [ 8), seen in Fig. 2c, can be used to show (6) From Fig. 2a.…”

Microstress Contrast in Scanning Electron Acoustic Microscopy of Ceramics

“…Although SEAM has been applied to the characterization of a wide variety of materials [7][8][9][10][11][12][13][14][15], only recently has it been applied to the assessment of brittle materials [16,17]. We have found [17] that SEAM images of Vickers indentations of SiC whisker-reinforced alumina clearly reveal not only the radial cracks, the length of which can be used to assess the fracture toughness of the material, but also reveal strong contrast, interpreted as arising from the combined effects of lateral cracks and the residual stress field left in the SiC whisker-reinforced alumina by the indenter.…”