Title :
Ultrasonic couplants for acoustic microscopy of low speed materials
Author :
Ardebili, Vahid Safavi ; Sinclair, Anthony N. ; Spelt, Jan K.
Author_Institution :
Dept. of Mech. Eng., Toronto Univ., Ont., Canada
Abstract :
A method is presented for estimating the compression wave velocities of organic fluids, based only on their density and molecular properties. The method is applied to a search for very low-speed ultrasonic couplants, suitable for 250 MHz acoustic microscopy studies of epoxy materials. Experimental measurements confirmed that acoustic velocity could be predicted within 3% for simple fluorine-containing organic compounds, and within 10% for those with a more complex molecular structure. The compound 2-dichloropentafluoropropane (C/sub 3/HCl/sub 2/F/sub 5/), with a compression wave velocity of C/sub L/=638 m/s and acceptably low attenuation coefficient, was identified as a good coupling agent for acoustic microscopy studies of low speed materials.
Keywords :
acoustic materials; acoustic microscopy; organic compounds; ultrasonic velocity measurement; 2-dichloropentafluoropropane; 250 MHz; acoustic microscopy; attenuation coefficient; compression wave velocity; density; epoxy material; low speed material; molecular structure; organic fluid; ultrasonic couplant; Acoustic materials; Acoustic measurements; Acoustic waves; Attenuation; Microscopy; Organic materials; Surface acoustic waves; Ultrasonic variables measurement; Velocity measurement; Water pollution;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on