Title :
Phonon focusing and the martensitic phase transformation in NiAl
Author :
Potashnik, S. ; Tulenko, A. ; Stenger, T.E. ; Trivisonno, J.
Author_Institution :
Dept. of Phys., John Carroll Univ., Cleveland, OH, USA
Abstract :
A modified scanning acoustic microscope was employed to study the effect of elastic anisotropy on the propagation of acoustic wavefronts in two NixAl1-x single crystal alloys with Ni compositions of 50 and 63 at.%. Both the longitudinal and slow transverse modes were studied. For the slow transverse mode large focusing effects and internal diffraction were observed for wavefronts on a 〈100〉 surface. Ultrasonic images were also studied as a function of temperature through the martensitic phase transformation in the Ni63Al37 crystal.
Keywords :
acoustic microscopy; aluminium alloys; elastic constants; martensitic transformations; nickel alloys; phonons; shape memory effects; ultrasonic focusing; ultrasonic imaging; ultrasonic propagation; Ni63Al37; NiAl; acoustic wavefronts propagation; elastic anisotropy effect; internal diffraction; large focusing effects; longitudinal modes; martensitic phase transformation; modified scanning acoustic microscope; phonon focusing; shape memory alloys; single crystal alloys; slow transverse modes; ultrasonic images; Acoustic diffraction; Acoustic propagation; Acoustic waves; Aluminum alloys; Anisotropic magnetoresistance; Focusing; Microscopy; Nickel alloys; Phonons; Surface waves;
Conference_Titel :
Ultrasonics Symposium, 1999. Proceedings. 1999 IEEE
Conference_Location :
Caesars Tahoe, NV
Print_ISBN :
0-7803-5722-1
DOI :
10.1109/ULTSYM.1999.849457
