Use of impulse excitation technique for the characterization of the elastic anisotropy of pharmaceutical tablets

2021 ◽  
pp. 120797
Author(s):  
J. Meynard ◽  
F. Amado-Becker ◽  
P. Tchoreloff ◽  
V. Mazel
Keyword(s):  
Elastic Anisotropy ◽  
Pharmaceutical Tablets ◽  
Impulse Excitation

scholarly journals In-situ characterization of growth of isothermal ω phase in metastable β-Ti alloy TIMETAL LCB

2020 ◽  
Vol 321 ◽  
pp. 11037
Author(s):  
J. Nejezchlebova ◽  
L. Bodnarova ◽  
M. Janovska ◽  
P. Sedlak ◽  
H. Seiner ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Elastic Constants ◽  
Elastic Anisotropy ◽  
Solid Phase ◽  
In Situ Observation ◽  
Ω Phase ◽  
Resonant Ultrasound ◽  
Isothermal Ageing

Metastable β-Ti alloys exhibit various solid-solid phase transitions. Our study is focused on the characterization of the diffusion controlled β→ωiso phase transition. The particles of ω phase play an important part in thermomechanical treatment since they serve as heterogeneous nucleation sites for precipitation of finely dispersed particles of hexagonal α phase. The in-situ observation of the growth of particles of ω phase could be difficult by conventional techniques. However, it was shown recently that the ω phase significantly influences the elastic constants of the material, and the different forms of ω phase have different effects on the elastic anisotropy, as well as on the internal friction coefficients. Therefore, the β→ω phase transformation could be in-situ observed by the precise measurement of the tensor of elastic constants. In this contribution, we present the study of the kinetics of the β→ωiso phase transformation by resonant ultrasound spectroscopy. The polycrystalline samples of TIMETAL LCB alloy were in-situ examined by this technique during isothermal and non-isothermal ageing at temperatures up to 300 °C.

Ultrasonic approach for viscoelastic and microstructure characterization of granular pharmaceutical tablets

2013 ◽  
Vol 454 (1) ◽  
pp. 333-343 ◽  
Author(s):  
Armin Saeedi Vahdat ◽  
Chaitanya Krishna Prasad Vallabh ◽  
Bruno C. Hancock ◽  
Cetin Cetinkaya
Keyword(s):  
Microstructure Characterization ◽  
Pharmaceutical Tablets

Another perspective on elastic and plastic anisotropy of textured metals

2021 ◽  
Vol 477 (2249) ◽  
pp. 20210234
Author(s):  
Aleksander Zubelewicz
Keyword(s):  
Plastic Flow ◽  
Elastic Strain ◽  
Elastic Anisotropy ◽  
Plastic Anisotropy ◽  
Complete Characterization ◽  
Tensor Representations ◽  
Supplementary Material ◽  
Elastic Responses ◽  
Preferential Pathways

In textured metals, the elastic directionality reflects the crystallographic organization, while the plastic flow follows the preferential pathways of deformation beyond the elastic limit. In here, the elastic and plastic anisotropies are characterized by two observers. One of them is immersed into the material and, while there, is unaware of the texture-induced reorganizations, still, is in a position to detect elastic distortions. Another observer is located outside the material, monitors the elastic strain too and realizes that texture makes the elastic responses directional. The externally measured elastic strain will be called the texture strain. The key idea is to determine the transformation rules that correlate the elastic strains seen by the two observers. In what follows, the rules are derived by projecting the texture-distorted basis onto the basis of the external observations. It turns out that the rules reproduce directionality of elastic properties and include constraints that result from the limits imposed by the yield stress. The elastic anisotropy is linked to the strain that is free of the plasticity-induced constraints. By contrast, the constraints enable complete characterization of the plastic flow directionality. The concept is derived in the framework of tensor representations discussed in the electronic supplementary material.

Comparison between permeability anisotropy and elasticity anisotropy of reservoir rocks

Geophysics ◽  
2002 ◽  
Vol 67 (1) ◽  
pp. 230-240 ◽  
Author(s):  
Patrick N. J. Rasolofosaon ◽  
Bernard E. Zinszner
Keyword(s):  
Elastic Anisotropy ◽  
Rock Permeability ◽  
X Ray ◽  
Reservoir Rocks ◽  
Invasion Fronts ◽  
Hydraulic Anisotropy ◽  
Elasticity Tensors ◽  
Complete Set ◽  
Seismic Measurements

We developed new experimental and theoretical tools for the measurement and the characterization of arbitrary elasticity tensors and permeability tensors in rocks. They include an experimental technique for the 3‐D visualization of hydraulic invasion fronts in rock samples by monitoring the injection of salt solutions by X‐ray tomography, and a technique for inverting the complete set of the six coefficients of the permeability tensor from invasion front images. In addition, a technique for measuring the complete set of the 21 elastic coefficients, a technique allowing the identification and the orientation in the 3‐D space of the symmetry elements (planes, axes), and a technique for approximating the considered elastic tensor by a tensor of simpler symmetry with the quantification of the error induced by such an approximation have been developed. We apply these tools to various types of reservoir rocks and observed quite contrasted behaviors. In some rocks, the elastic anisotropy and the hydraulic anisotropy are closely correlated, for instance in terms of the symmetry directions. This is the case when elastic anisotropy and hydraulic anisotropy share the same cause (e.g., layering, fractures). In contrast, in some other rocks, hydraulic properties and elastic properties are clearly uncorrelated. These results highlight the challenge we have to face in order to estimate the rock permeability and to monitor the fluid flow from seismic measurements in the field.

scholarly journals On the evolution of the elastic properties of organic-rich shale upon pyrolysis-induced thermal maturation

Geophysics ◽  
2016 ◽  
Vol 81 (3) ◽  
pp. D263-D281 ◽  
Author(s):  
Adam M. Allan ◽  
Anthony C. Clark ◽  
Tiziana Vanorio ◽  
Waruntorn Kanitpanyacharoen ◽  
Hans-Rudolf Wenk
Keyword(s):  
Elastic Properties ◽  
Elastic Anisotropy ◽  
Time Lapse ◽  
Source Rocks ◽  
Thermal Maturity ◽  
Thermal Maturation ◽  
Confining Pressures ◽  
Acoustic Velocities

The evolution of the elastic properties of organic-rich shale as a function of thermal maturity remains poorly constrained. This understanding is pivotal to the characterization of source rocks and unconventional reservoirs. To better constrain the evolution of the elastic properties and microstructure of organic-rich shale, we have studied the acoustic velocities and elastic anisotropy of samples from two microstructurally different organic-rich shales before and after pyrolysis-induced thermal maturation. To more physically imitate in situ thermal maturation, we performed the pyrolysis experiments on intact core plugs under applied reservoir-magnitude confining pressures. Iterative characterization of the elastic properties of a clay-rich, laminar Barnett Shale sample documents the development of subparallel to bedding cracks by an increase in velocity sensitivity to pressure perpendicular to the bedding. These cracks, however, are not visible through time-lapse scanning electron microscope imaging, indicating either submicrometer crack apertures or predominant development within the core of the sample. At elevated confining pressures, in the absence of pore pressure, these induced cracks close, at which point, the sample is acoustically indistinguishable from the prepyrolysis sample. Conversely, a micritic Green River sample does not exhibit the formation of aligned compliant features. Rather, the sample exhibits a largely directionally independent decrease in velocity as load-bearing, pore-filling kerogen is removed from the sample. Due to the weak alignment of minerals, there is comparatively little intrinsic anisotropy; further, due to the relatively directionally independent evolution of velocity, the evolution of the anisotropy as a function of thermal maturity is not indicative of aligned compliant features. Our results have indicated that horizons of greater thermal maturity may be acoustically detectable in situ through increases in the elastic anisotropy of laminar shales or decreases in the acoustic velocities of nonlaminar shales, micritic rocks, or siltstones.

The Role Of Grain Noise In Eddy Current Inspection Of Titanium Alloys

1997 ◽  
Vol 503 ◽  
Author(s):  
M. P. Blodgett ◽  
P. B. Nagy
Keyword(s):  
Titanium Alloys ◽  
Eddy Current ◽  
Crack Detection ◽  
Elastic Anisotropy ◽  
Acoustic Noise ◽  
Electrical Anisotropy ◽  
Integrity Assessment ◽  
Ultrasonic Characterization ◽  
Eddy Current Inspection

ABSTRACTThis paper discusses the role electrical anisotropy plays in the structural integrity assessment of polycrystalline titanium alloys from the standpoint of fatigue crack detection and the related issue of microstructural noise. In eddy current inspection of noncubic crystallographic classes of polycrystalline metals the electric anisotropy of individual grains produces an inherent microstructural variation or noise that is very similar to the well-known acoustic noise produced by the elastic anisotropy of both cubic and noncubic materials in ultrasonic characterization. The presented results demonstrate that although the electrical grain noise is detrimental in eddy current nondestructive testing for small flaws, it can be also exploited for characterization of the microstructure in noncubic polycrystalline materials such as titanium alloys in the same way acoustic grain noise is used for ultrasonic characterization of the microstructure in different materials.

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