Scanning acoustic microscopy

Applications. Nondestructive method of determination of carbon fiber reinforced composites. Damage of woven fiber reinforced composites, distribution of filler due to flow in molding techniques, distribution of fiber in composite, and dispersion of carbon black are examples characterizing potential applications of the method. 

Major results. The method is useful for control of expensive materials in responsible applications, such as, for example, materials used in aeronautics. Material control or inspection can be conducted (pulse method) without damage caused to the inspected material. The other essential advantage of the method is related to the fact that fillers can be observed within the filled material, which is not possible by any other technique. In addition, clarity of the micrograph is improved compared with optical microscopy. This method, although unique, has many applications in filled materials and hopefully more data will be known in the future in order to facilitate better understanding of filled materials. 

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The brief history, operation principle, and applications of the above-mentioned techniques are described in this chapter. There are several other measuring techniques, such as the fluorometry technique. Scanning Acoustic Microscopy, Laser Doppler Vibrometer, and Time-of-flight Secondary Ion Mass Spectroscopy, which are successfully applied in micro/nanotribology, are introduced in this chapter, too. 

Scanning acoustic microscopy (SAM) is a relatively new technique which broke through in the mid-seventies and was commercialized recently. The SAM uses sound to create visual images of variations in the mechanical properties of samples. The ability of acoustic waves to penetrate optically opaque materials makes it possible to provide surface or subsurface stmctural images nondestmctively, which might... 

Blau, P. J., and Simpson, W. A., Applications of Scanning Acoustic Microscopy in Analyzing Wear and Single-Point Abrasion Damage, Wear, Vol. 181-183,1995, pp. 405 12. 

The Li-Loos intimate contact model was verified for compression molded unidirectional graphite-polysulfone and graphite-PEEK (APC-2) laminae and graphite-PEEK (APC-2) cross-ply laminates. The degrees of intimate contact of the unidirectional and cross-ply specimens were measured by optical microscopy and scanning acoustic microscopy, respectively. The predicted degrees of intimate contact agreed well with the measured values for both the unidirectional and cross-ply specimens processed at different temperature and pressures. 

In the following example, scanning acoustic microscopy is combined with optical microscopy to measure intimate contact at the ply interfaces of a [0o/90o/0°]r graphite-PEEK laminate. First, eight holes, 1.5 mm (0.059 in.) in diameter, were drilled into the composite specimen. These holes, shown in Figure 7.12, were used to locate where on the composite specimen the scanning acoustic microscope images were taken. 

The intimate contact data shown in Figure 7.16 were obtained from three-ply, APC-2, [0°/90o/0o]7- cross-ply laminates that were compression molded in a 76.2 mm (3 in.) square steel mold. The degree of intimate contact of the ply interfaces was measured using scanning acoustic microscopy and image analysis software (Section 7.4). The surface characterization parameters for APC-2 Batch II prepreg in Table 7.2 and the zero-shear-rate viscosity for PEEK resin were input into the intimate contact model for the cross-ply interface. Additional details of the experimental procedures and the viscosity data for PEEK resin are given in Reference 22. 

Bereiter-Hahn, J. (1987). Scanning acoustic microscopy visualizes cytomechanical responses to cytochalasin D. J. Microsc. 146, 29-39. [161-3]... 

Briggs, G. A. D. (1984). Scanning electron acoustic microscopy and scanning acoustic microscopy a favourable comparison. Scanning Electron Microsc. 3, 1041-52. [17]... 

Briggs, G. A. D. (1985). An introduction to scanning acoustic microscopy, Royal Microscopical Society Handbook, no. 12. Oxford University Press, Oxford, [xi, 46]... 

Burton, N. J Thaker, D. M., and Tsukamoto, S. (1985). Recent developments in the practical and industrial applications of scanning acoustic microscopy. Ultrasonics Int. 85, 334-8. [199]... 

Hoppe, M. and Bereiter-Hahn, J. (1985). Applications of scanning acoustic microscopy—survey and new aspects. IEEE Trans. SU-32, 289-301. [11, 25, 202, 218]... 

Jenkins, P. J. (1990) Scanning acoustic microscopy of persistent slip bands. In EMAG-MICRO 89 (ed. H. Y. Elder and P. J. Goodhew), Inst. Phys. Conf. Ser. 98, pp. 153-6. Institute of Physics, Bristol. [282]... 

Litniewski, J. and Bereiter-Hahn, J. (1990), Measurements of cells in culture by scanning acoustic microscopy. J. Microsc. 158, 95-107. [165,169,171]... 

Matthaei, E., Vetters, H., and Mayr, P. (1990). Reflective scanning acoustic microscopy for imaging subsurface structures in solid state materials. In Advanced materials and processes (ed. H. E. Exner and V. Schumacher), pp. 1415-20. DGM Informationsge-sellschaft mbH, Oberursel. [200, 219]... 

Nagy, P. B. and Adler, L. (1989). On the origin of increased backward radiation from a liquid-solid interface at the Rayleigh angle. J. Acoust. Soc. Am. 85,1355-7. [116] Narita, T., Miura, K., Ishikawa, I., and Ishikawa, T. (1990). Measurement of residual thermal stress and its distribution on silicon nitride ceramics joined to metals with scanning acoustic microscopy. /. Japan. Inst. Metals 54,1142-6. [148]... 

Nikoonahad, M. and Liu, D. C. (1990). Pulse-echo single frequency acoustic nonlinearity parameter (B/A) measurement. IEEE Trans. UFFC 37, 127-34. [43, 181] Nikoonahad, M. and Sivers, E. A. (1989). Dual beam differential amplitude contrast scanning acoustic microscopy. In Acoustical imaging, Vol. 17 (ed. H. Shimizu, N. Chubachi, and J. Kushibiki), pp. 17-25. Plenum Press, New York. [69]... 

Revay, L., Lindblad, G., and Lind, L. (1990). IC package defects revealed by scanning acoustic microscopy (SAM). CERT 90 Components engineering, Reliability and Test Conference (Electron. Components Inst.), pp. 115-22. [199]... 

Tsai, C. S. and Lee, C. C. (1987). Nondestructive imaging and characterization of electronic materials and devices using scanning acoustic microscopy. In Pattern recognition and acoustical imaging (ed. L. A. Ferrari). SPIE 768,260-6. [ 110,202] Tsukahara, Y. and Ohira, K. (1989). Attenuation measurements in polymer films and coatings by ultrasonic spectroscopy. Ultrasonics Int. 89, 924-9. [204]... 

Wang, J. K Tsai, C. S., and Lee, C. C. (1980). Spectroscopic study of defects in thick specimen using transmission scanning acoustic microscopy. In Scanned image microscopy (ed. E. A. Ash), pp. 137-47. Academic Press, London. [110]... 

This chapter describes the results of an ongoing study we are conducting into the nanoscale mechanical properties, chemical composition and structure of healthy enamel, carious lesions and the acquired salivary pellicle layer. A variety of material characterization techniques are being used, including nanoindentation, scanning electron microscopy (SEM), electron microprobe analysis (EMPA), scanning acoustic microscopy, atomic force microscopy (AFM) and time-of-flight secondary ion mass spectroscopy (TOF SIMS). 

Fourier transform infrared spectroscopy (FTIR) ASTM E1421 Elongation tests Scanning electronic microscopy (SEM) Differential scanning calorimetry (DSC) ASTM D3417 Scanning acoustic microscopy (SAM)... 

Applications The physical principle of measurement is similar to the scanning acoustic microscopy discussed in the Section 14.23, but applications and the method of data processing are essentially different. Sonic methods were used in the following applications to filled materials the effect of particle size and surface treatment on acoustic emission of filled epoxy, longitudinal velocity measurement of tungsten filled epoxy, and in-line ultrasonic measurement of fillers during extrusion. Numerous parameters related to fillers can be characterized by this non-destructive method. 

A nondestructive thermoacoustic material signature (TAMS) imaging method in scanning acoustic microscopy (SAM) was recently utilized to study the matrix and tempers signatures of ancient ceramics (90). 

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