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Hassel Ledbetter - One of the best experts on this subject based on the ideXlab platform.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite (α-TeO 2 ). Tetragonal paratellurite (D 4 4,P422) shows six independent elastic constants C i j k l , the associated Internal Friction Q - 1 ijkl, and one piezoelectric coefficient e 1 4 . We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our C i j k l were consistent with reported values measured by conventional methods. Our e 1 4 exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the C i j k l temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Hirotsugu Ogi, Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite $(\ensuremath{\alpha}\ensuremath{-}{\mathrm{TeO}}_{2}).$ Tetragonal paratellurite ${(D}_{4}^{4},P422)$ shows six independent elastic constants ${C}_{\mathrm{ijkl}},$ the associated Internal Friction ${Q}_{\mathrm{ijkl}}^{\ensuremath{-}1},$ and one piezoelectric coefficient ${e}_{14}.$ We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our ${C}_{\mathrm{ijkl}}$ were consistent with reported values measured by conventional methods. Our ${e}_{14}$ exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the ${C}_{\mathrm{ijkl}}$ temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
Masashi Fukunaga - One of the best experts on this subject based on the ideXlab platform.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite (α-TeO 2 ). Tetragonal paratellurite (D 4 4,P422) shows six independent elastic constants C i j k l , the associated Internal Friction Q - 1 ijkl, and one piezoelectric coefficient e 1 4 . We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our C i j k l were consistent with reported values measured by conventional methods. Our e 1 4 exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the C i j k l temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Hirotsugu Ogi, Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite $(\ensuremath{\alpha}\ensuremath{-}{\mathrm{TeO}}_{2}).$ Tetragonal paratellurite ${(D}_{4}^{4},P422)$ shows six independent elastic constants ${C}_{\mathrm{ijkl}},$ the associated Internal Friction ${Q}_{\mathrm{ijkl}}^{\ensuremath{-}1},$ and one piezoelectric coefficient ${e}_{14}.$ We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our ${C}_{\mathrm{ijkl}}$ were consistent with reported values measured by conventional methods. Our ${e}_{14}$ exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the ${C}_{\mathrm{ijkl}}$ temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
Masahiko Hirao - One of the best experts on this subject based on the ideXlab platform.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite (α-TeO 2 ). Tetragonal paratellurite (D 4 4,P422) shows six independent elastic constants C i j k l , the associated Internal Friction Q - 1 ijkl, and one piezoelectric coefficient e 1 4 . We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our C i j k l were consistent with reported values measured by conventional methods. Our e 1 4 exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the C i j k l temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
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elastic constants Internal Friction and piezoelectric coefficient of α teo 2
Physical Review B, 2004Co-Authors: Hirotsugu Ogi, Masashi Fukunaga, Masahiko Hirao, Hassel LedbetterAbstract:We studied the interrelationship of elastic and piezoelectric properties with the lattice structure and crystal physics of paratellurite $(\ensuremath{\alpha}\ensuremath{-}{\mathrm{TeO}}_{2}).$ Tetragonal paratellurite ${(D}_{4}^{4},P422)$ shows six independent elastic constants ${C}_{\mathrm{ijkl}},$ the associated Internal Friction ${Q}_{\mathrm{ijkl}}^{\ensuremath{-}1},$ and one piezoelectric coefficient ${e}_{14}.$ We determined simultaneously these material coefficients using resonant ultrasound spectroscopy coupled with laser-Doppler interferometry. Mode identification, essential for success, was done by measuring the displacement distributions on a vibrating-specimen surface. Our ${C}_{\mathrm{ijkl}}$ were consistent with reported values measured by conventional methods. Our ${e}_{14}$ exceeds the reported value by 53%. We focus on several unusual elastic properties, including a negative Poisson ratio. Considering a star-shape truss structure on the basal plane consistently explains all of them. Internal Friction correlates with the ${C}_{\mathrm{ijkl}}$ temperature derivatives, suggesting phonon-phonon interactions as a dominant cause of the mechanical loss.
Shigeru Asano - One of the best experts on this subject based on the ideXlab platform.
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solid solution hardening evaluated from amplitude dependent Internal Friction in polycrystalline copper alloys
Scripta Materialia, 1999Co-Authors: Naoki Ide, Motochika Yamashita, Shigeru AsanoAbstract:In the present study, the authors evaluated plastic strain as a function of stress from data of the amplitude-dependent Internal Friction in polycrystalline Cu alloys under the condition that the flow stress is controlled only by the mobility of dislocations. The polycrystalline alloys were employed as specimens in the measurements, because the amplitude dependence of Internal Friction is too structure-sensitive to show reproducible results in highly pure monocrystals. In addition, the application of the present evaluation of plastic strain to engineering materials is expected as a new non-destructive strength test. The solute elements were restricted within IVb group and the concentration was fixed at 0.3% in order to examine the dependence of flow stress on the size misfit between solute and solvent atoms.
Ward L Johnson - One of the best experts on this subject based on the ideXlab platform.
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elastic constants and Internal Friction of martensitic steel ferritic pearlitic steel and α iron
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2007Co-Authors: Sudook Kim, Ward L JohnsonAbstract:Abstract The elastic constants and Internal Friction of induction hardened and unhardened SAE 1050 plain-carbon steel at ambient temperatures were determined by resonant ultrasonic spectroscopy. The hardened specimen contained only martensite and the unhardened specimen was ferrite-pearlite. Using an inverse Ritz algorithm with assumed orthorhombic symmetry, all nine independent elastic-stiffness coefficients were determined, and, from the resonance peak widths, all nine components of the Internal-Friction tensor were determined. Similar measurements and analysis on monocrystalline α-iron were performed. The steel has slight elastic anisotropy, and the isotropically approximated elastic moduli were lower in the martensite than in ferrite-pearlite: shear modulus by 3.6%, bulk modulus by 1.2%, Young modulus by 3.2%, and Poisson ratio by 1.5%. Isotropically approximated elastic moduli of α-iron were 0.6–1.3% higher than ferrite-pearlite. All components of the Internal-Friction in martensite were higher than those of ferrite-pearlite, but lower than those of α-iron.
