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43918 Effect of microstructural damage on ultrasonic velocity and elastic moduli of partially stabilized zirconia
ND T Abstracts 43933 Fitting, D.W.; Kriz, R.D.; Clark, A.V. M e a s u r i n g in-plane elastic moduli of composites with a r r a y s of phase- insensitive u l t r a s o u n d receivers Proceedings of the 15th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, California (USA), 31 Jul. - 5 Aug. 1988. Vol. 8B, pp. 1497-1504. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1989). ISBN 0-306-43209-9. A phase-insensitive array has been developed for rapid nondestructive measurement of in-plane elastic moduli. The array characteristics allow for determination of energy flux deviation angle in the composite, as well as measurement of group and phase velocity. Techniques for computing the phase velocity from array measurements are described. Energy flux deviation in unidirectional graphite-epoxy specimens has been determined with the array. Comparisons are made herein of results with analytical (bulk wave) predictions.
42856 Rokhlin, S.I.; Wang, W. Critical angle m e a s u r e m e n t of elastic c o n s t a n t s in composite
material Journal of the Acoustical Society of America, Vol. 86, No. 5. pp. 1876- 1882 (Nov. 1989) Application of critical angle measurement for determination of elastic constants of composite materials is described. It is shown that, for any two-dimensional composite material, the critical angles are directly related to the phase velocities of bulk waves in the sample plane. A simple and novel type of goniometer is developed for these measurements which utilize a cylindrical reflector for measurement of the double reflection coefficient. The values of the elastic constants are reconstructed from the measured velocity surfaces by using nonlinear least-squares optimization fitting. Analytical relations between ultrasonic velocity and elastic constants valid for arbitrary anisotropy are implemented in the fitting optimization.
Varughese, J.V.; Wolfenden, A.; Ludtka, G.M. Temperature dependence of dynamic Young's and shear moduli for four different heat treated conditions of depleted U-2Mo 42845
Rogers, W.P.; lsaacs, J.; Nemat-Nasser, S. Effect of microstructural damage on ultrasonic velocity and elastic moduli of partially stabilized zirconia
43918
Proceedings of the 15th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, California (USA), 31 J u l . - 5 Aug. 1988. Vol. 8B, pp. 1827-1832. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1989). ISBN 0-306-43209-9. Ultrasonic testing can aid in the characterization of microstroctural changes associated with transformation plasticity. The present paper presents measurements of ultrasonic velocity as a function of microstructural damage in Mg-PSZ loaded in compression at high strain rates. Observed changes in elastic moduli are compared to a model of a solid containing randomly distributed penny-shaped microcracks which are all oriented parallel to the axis of compression. 43874 Castagnede, B.; Jenkins, J.T.; Sachse, W.; Baste, S. O p t i m a l determination of the elastic constants of composite
materials from ultrasonic wave-speed measurements Journal of Applied Physics, Vol. 67, No. 6, pp. 2753-2761 (15 Mar. 1990) A method is described to optimally determine the elastic constants of anisotropic solids from wave-speeds measurements in arbitrary nonprincipal planes. For such a problem, the characteristic equation is a degree-three polynomial which generally does not factorize. By developing and rearranging this polynomial, a nonlinear system of equations is obtained. The elastic constants are then recovered by minimizing a functional are given for two specific overdetermined system of equations. Calculations of the functional are given for two specific cases, i.e., the orthorhombic and the hexagonal symmetries. Some numerical results showing the efficiency of the algorithm are presented. A numerical method is also described for the recovery of the orientation of the principal acoustical axes. This problem is solved through a double-iterative numerical scheme. Numerical as well as experimental results are presented for a unidirectional composite material.
Rosenberg, R. Elasticity and sliding modules determined in metals and ceramics. (In German, English abstract)
43157
Materialprufung, Vol. 32, No. 1-2, pp. 16-17 (Jan. 1990) For the quality assurance with development and manufacturing, the longitudinal and transversal wave speed is measured on test specimens, among other things. The results obtained permit a simple calculation of the material parameters, module of elasticity and sliding module, which contribute to determine the Ioadability.
Castagnede, B.; Sachse, W.; Thompson, M.O. Determination of the elastic constants of anisotropic m a t e r i a l s via laser-generated ultrasound
42937
Proceedings of Ultrasonics International 89, Madrid (Spain), 3-7 July 1989, pp. 71-77, Butterworth Scientific Ltd. ISBN 0408054182 (1989) This paper presents the solution of the inverse anisotropic medium problem in which the elastic constants of an anisotropic material are determined from ultrasonic wavespeed measurements made in non-principal directions of a specimen. The ultrasonic waves were generated via the point-source/point-receiver technique using a pulsed laser as a source and a miniature, point-like transducer as a receiver. Experimental results are presented for a transversely isotropic composite material and a single crystal specimen of Silicon. It was found that the non- linear fit between the experimental and the recovered slowness values is excellent.
52
N D T & E International 1994 Volume 27, Number 1
Journal of Testing and Evaluation, Vol. 17, No. 6, pp. 329-332 (Nov. 1989) Dynamic Young's and shear moduli measurements were made for depleted U- 2Mo alloys. The experimental technique used was the PUCOT (Piezoelectric Ultrasonic Composite Oscillator Technique). Experiments were performed on four different heat treatments of the alloy from ambient temperature to 800(2 in 50(2 increments. 42828 Delsanto, P.P.; Quarati, P.; Boschetti, F.; Chaskelis, H.H.; Mognogna, R.B. Ultrasonic determination of elastic constants in metal alloys Proceedings of the International Conference on Monitoring, Surveillance and Predictive Maintenance of Plants and Structures, Taormina-Giardini Naxos, Sicily (Italy), 15-18 Oct. 1989. pp. 348-354, Italian Society for Nondestructive Testing The characterization of polycrystalline materials, such as AI-Li alloys, requires the determination of the elastic constants, texture and residual stress and the detection and evaluation of flaws and irregularities, Instead of a complete characterization, it is sometimes sufficient to determine "effective" elastic constants, e.g. values of the ~ constants or of the Poisson's ratio and Young's modulus, which include the effects of both texture and stress. In this contribution, we present an ultrasonic method for the determination of effective elastic constants. The results are compared with those of extensimetric measurements. 42580 Higazy, A.A.; Bridge, B.; Hussein, A.; Ewaida, M.A. Elastic c o n s t a n t s a n d s t r u c t u r e of the vitreous system Z n O P/sub2/O/sub5/ Journal of the Acoustic Society of America, Vol. 86, No. 4, pp. 1453- 1458 (Oct. 1989) The elastic moduli of the entire vitreous range of the system ZnO-PO that can be prepared by melting ZnO and PO oxides in open crucibles have been measured by ultrasonic techniques, The bulk, shear, longitudinal, and Young's moduli, and the Poisson's ratio are found to be rather sensitive to the glass composition. From these ul~asonic data, it is found that the glass system can he divided into "three compositional regions". This behaviour is qualitatively interpreted in terms of the zinc coordination, cross-link densities, and interatomic force constants.
Lebedev, A.B.; Burenkov, Yu.A.; lvanov, V.I.; Kardashev, B.K.; Nikanorov, S.P.; Stepanov, Yu.P. Amplitude and temperature dependencies of ultrasound absorption and of Young's Modulus in a YBaCuO superconducting ceramic
42432
Russian Ultrasonics, Vol. 19, No. 1, pp. 40-44 (1989) Studies of the oscillatery deformation of the high temperature superconducting ceramic YBaCuO are described in this paper. A resonance method was used with a composite piezoelectric longitudinal wave vibrator on a rod sample. The study focuses especially on the temperature dependence of ultrasound absorption and of Young's Modulus for the ceramic rod. Explanations for certain features of these characteristics are suggested. 42401 Norris, A.N. On the acoustic determination of the elastic moduli of anisotropic solids and acoustic conditions for the existence of s y m m e t r y planes Quarterly Journal of Mechanics and Applied Mathematics, Vol. 42, Pt. 3, pp. 413-426 (Aug. 1989)
42856 Rokhlin, S.I.; Wang, W. Critical angle m e a s u r e m e n t of elastic c o n s t a n t s in composite
material Journal of the Acoustical Society of America, Vol. 86, No. 5. pp. 1876- 1882 (Nov. 1989) Application of critical angle measurement for determination of elastic constants of composite materials is described. It is shown that, for any two-dimensional composite material, the critical angles are directly related to the phase velocities of bulk waves in the sample plane. A simple and novel type of goniometer is developed for these measurements which utilize a cylindrical reflector for measurement of the double reflection coefficient. The values of the elastic constants are reconstructed from the measured velocity surfaces by using nonlinear least-squares optimization fitting. Analytical relations between ultrasonic velocity and elastic constants valid for arbitrary anisotropy are implemented in the fitting optimization.
Varughese, J.V.; Wolfenden, A.; Ludtka, G.M. Temperature dependence of dynamic Young's and shear moduli for four different heat treated conditions of depleted U-2Mo 42845
Rogers, W.P.; lsaacs, J.; Nemat-Nasser, S. Effect of microstructural damage on ultrasonic velocity and elastic moduli of partially stabilized zirconia
43918
Proceedings of the 15th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, California (USA), 31 J u l . - 5 Aug. 1988. Vol. 8B, pp. 1827-1832. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1989). ISBN 0-306-43209-9. Ultrasonic testing can aid in the characterization of microstroctural changes associated with transformation plasticity. The present paper presents measurements of ultrasonic velocity as a function of microstructural damage in Mg-PSZ loaded in compression at high strain rates. Observed changes in elastic moduli are compared to a model of a solid containing randomly distributed penny-shaped microcracks which are all oriented parallel to the axis of compression. 43874 Castagnede, B.; Jenkins, J.T.; Sachse, W.; Baste, S. O p t i m a l determination of the elastic constants of composite
materials from ultrasonic wave-speed measurements Journal of Applied Physics, Vol. 67, No. 6, pp. 2753-2761 (15 Mar. 1990) A method is described to optimally determine the elastic constants of anisotropic solids from wave-speeds measurements in arbitrary nonprincipal planes. For such a problem, the characteristic equation is a degree-three polynomial which generally does not factorize. By developing and rearranging this polynomial, a nonlinear system of equations is obtained. The elastic constants are then recovered by minimizing a functional are given for two specific overdetermined system of equations. Calculations of the functional are given for two specific cases, i.e., the orthorhombic and the hexagonal symmetries. Some numerical results showing the efficiency of the algorithm are presented. A numerical method is also described for the recovery of the orientation of the principal acoustical axes. This problem is solved through a double-iterative numerical scheme. Numerical as well as experimental results are presented for a unidirectional composite material.
Rosenberg, R. Elasticity and sliding modules determined in metals and ceramics. (In German, English abstract)
43157
Materialprufung, Vol. 32, No. 1-2, pp. 16-17 (Jan. 1990) For the quality assurance with development and manufacturing, the longitudinal and transversal wave speed is measured on test specimens, among other things. The results obtained permit a simple calculation of the material parameters, module of elasticity and sliding module, which contribute to determine the Ioadability.
Castagnede, B.; Sachse, W.; Thompson, M.O. Determination of the elastic constants of anisotropic m a t e r i a l s via laser-generated ultrasound
42937
Proceedings of Ultrasonics International 89, Madrid (Spain), 3-7 July 1989, pp. 71-77, Butterworth Scientific Ltd. ISBN 0408054182 (1989) This paper presents the solution of the inverse anisotropic medium problem in which the elastic constants of an anisotropic material are determined from ultrasonic wavespeed measurements made in non-principal directions of a specimen. The ultrasonic waves were generated via the point-source/point-receiver technique using a pulsed laser as a source and a miniature, point-like transducer as a receiver. Experimental results are presented for a transversely isotropic composite material and a single crystal specimen of Silicon. It was found that the non- linear fit between the experimental and the recovered slowness values is excellent.
52
N D T & E International 1994 Volume 27, Number 1
Journal of Testing and Evaluation, Vol. 17, No. 6, pp. 329-332 (Nov. 1989) Dynamic Young's and shear moduli measurements were made for depleted U- 2Mo alloys. The experimental technique used was the PUCOT (Piezoelectric Ultrasonic Composite Oscillator Technique). Experiments were performed on four different heat treatments of the alloy from ambient temperature to 800(2 in 50(2 increments. 42828 Delsanto, P.P.; Quarati, P.; Boschetti, F.; Chaskelis, H.H.; Mognogna, R.B. Ultrasonic determination of elastic constants in metal alloys Proceedings of the International Conference on Monitoring, Surveillance and Predictive Maintenance of Plants and Structures, Taormina-Giardini Naxos, Sicily (Italy), 15-18 Oct. 1989. pp. 348-354, Italian Society for Nondestructive Testing The characterization of polycrystalline materials, such as AI-Li alloys, requires the determination of the elastic constants, texture and residual stress and the detection and evaluation of flaws and irregularities, Instead of a complete characterization, it is sometimes sufficient to determine "effective" elastic constants, e.g. values of the ~ constants or of the Poisson's ratio and Young's modulus, which include the effects of both texture and stress. In this contribution, we present an ultrasonic method for the determination of effective elastic constants. The results are compared with those of extensimetric measurements. 42580 Higazy, A.A.; Bridge, B.; Hussein, A.; Ewaida, M.A. Elastic c o n s t a n t s a n d s t r u c t u r e of the vitreous system Z n O P/sub2/O/sub5/ Journal of the Acoustic Society of America, Vol. 86, No. 4, pp. 1453- 1458 (Oct. 1989) The elastic moduli of the entire vitreous range of the system ZnO-PO that can be prepared by melting ZnO and PO oxides in open crucibles have been measured by ultrasonic techniques, The bulk, shear, longitudinal, and Young's moduli, and the Poisson's ratio are found to be rather sensitive to the glass composition. From these ul~asonic data, it is found that the glass system can he divided into "three compositional regions". This behaviour is qualitatively interpreted in terms of the zinc coordination, cross-link densities, and interatomic force constants.
Lebedev, A.B.; Burenkov, Yu.A.; lvanov, V.I.; Kardashev, B.K.; Nikanorov, S.P.; Stepanov, Yu.P. Amplitude and temperature dependencies of ultrasound absorption and of Young's Modulus in a YBaCuO superconducting ceramic
42432
Russian Ultrasonics, Vol. 19, No. 1, pp. 40-44 (1989) Studies of the oscillatery deformation of the high temperature superconducting ceramic YBaCuO are described in this paper. A resonance method was used with a composite piezoelectric longitudinal wave vibrator on a rod sample. The study focuses especially on the temperature dependence of ultrasound absorption and of Young's Modulus for the ceramic rod. Explanations for certain features of these characteristics are suggested. 42401 Norris, A.N. On the acoustic determination of the elastic moduli of anisotropic solids and acoustic conditions for the existence of s y m m e t r y planes Quarterly Journal of Mechanics and Applied Mathematics, Vol. 42, Pt. 3, pp. 413-426 (Aug. 1989)