A convenient measuring technique is presented for determining ultrasonic attenuation and interface losses in a material for the purpose of equalizing testing sensitivity when using a calibration standard of different material than that to be tested. For attenuation measurements, this technique compensates for the effect of initial pulse amplitude, reflection and transmission coefficients due to impedance difference between the material and coupling medium. Also shown are illustrations of the effects of location of the transducer focal spot on the surface on which the beam is incident on ASTM and similar test blocks for various lengths and flat bottom hole targets within the material.
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