Title :
Acoustic characterization of metals with long needle grains
Author :
Jen, C.K. ; Soda, H. ; Liu, Y.S. ; Neron, C. ; Ohno, A. ; McLean, A.
Author_Institution :
IMI, Nat. Res. Council, Boucherville, Que., Canada
Abstract :
Acoustic characterization measurements of Sn, Pb, Al, and Cu metallic alloys with highly oriented long needle grains are presented. Using a 225-MHz line-focus-beam scanning acoustic microscope, the ultrasonic anisotropy of a transversely isotropic symmetry for samples having small primary dendrite spacings (~ acoustic wavelength) samples is observed. The column grain structures induce unique acoustic propagation characteristics, such as focusing and diverging, which are illustrated in the guided longitudinal and shear acoustic wave pulse-echo measurements performed for rod geometries
Keywords :
acoustic microscopy; aluminium; aluminium alloys; copper; copper alloys; lead; lead alloys; surface acoustic waves; tin; tin alloys; ultrasonic materials testing; ultrasonic velocity measurement; 225 MHz; Al; Al-Cu alloy; Cu; Pb; Sn; Sn-Pb alloy; acoustic characterisation; column grain structures; diverging; focusing; guided longitudinal waves; leaky SAW; line-focus-beam scanning acoustic microscope; long needle grains; metals; shear acoustic wave pulse-echo measurements; small primary dendrite spacings; transversely isotropic symmetry; ultrasonic anisotropy; Acoustic measurements; Acoustic waves; Aluminum alloys; Copper alloys; Microscopy; Needles; Pulse measurements; Tin; Ultrasonic variables measurement; Wavelength measurement;
Conference_Titel :
Ultrasonics Symposium, 1992. Proceedings., IEEE 1992
Conference_Location :
Tucson, AZ
Print_ISBN :
0-7803-0562-0
DOI :
10.1109/ULTSYM.1992.275899
