This Engineering Research Equipment proposal is for funds for a scanning acoustic microscope to conduct a broad range of studies in materials engineering, precision machining, physics, archaeometry, and fiber and polymer science. True acoustic microscopes are recent developments that now have a resolution equal to that of a light microscope. The important difference between light- and acoustic- microscopy is in the causes of image contrast. Contrast in light microscopy is due to the existence of and variations in optical indices of refraction and coefficients of optical absorption. These basic parameters are, in general, only indirectly related to the material's physical properties; whereas, with the acoustic microscope, contrast within the image is due to variation in the elastic, viscoelastic and density properties. The image is thus not dependent on visible light transmission. Specific problems on which the acoustic microscopy is to be used are: (1) to examine microscopic elastic and viscoelastic moduli and density variations in ultra-oriented fibers produced by flow-induced orientation and high-speed takeup; (2) to examine the interfacial regions using a non-destructive procedure in reducing the moisture absorption of epoxy resin/graphite fiber composites; (3) to characterize defects in semiconductor materials and in developing new image analysis techniques; (4) to investigate the interface during strain in polymer matrix composites (the novel utility here is due to the composites being opaque to light but still transparent to ultra- sound); (5) to assist the Precision Engineering Center (newly formed at this university) in the characterization of subsurface damage; and (6) to examine, count, and measure subsurface structures in archaeological specimens.
