Using neutron diffraction measurements to characterize the mechanical properties of polymineralic rocks

2003 ◽  
Vol 67 (5) ◽  
pp. 967-987 ◽  
Author(s):  
P. F. Schofield ◽  
S. J. Covey-Crump ◽  
I. C. Stretton ◽  
M. R. Daymond ◽  
K. S. Knight ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Neutron Diffraction ◽  
Deformation Behaviour ◽  
Theoretical Models ◽  
Rock Properties ◽  
Geological Materials ◽  
Wide Range ◽  
Diffraction Patterns ◽  
Elastic And Plastic Deformation

AbstractConventional experiments designed to investigate the mechanical properties of polycrystalline geological materials are generally restricted to measurements of whole-rock properties. However, when comparing the measurements with theoretical models, it is frequently essential to understand how the deformation is accommodated at the grain-scale. This is particularly true for polymineralic rocks because in this case most theories express the whole-rock properties as some function of the properties of their constituent minerals, and hence the contribution which each phase makes to those properties must be measured if the theories are to be fully assessed. The penetrating nature of neutrons offers a method of addressing this problem. By performing deformation experiments in the neutron beam-line and collecting neutron diffraction patterns at different applied loads, the lattice parameters of all the mineral phases present may be determined as a function of load. The elastic strain experienced by each phase is then easily determined. Moreover, the strain in different lattice directions is also obtained. From this information a wide range of problems relevant for the characterization of the elastic and plastic deformation behaviour of polymineralic geological materials can be explored. An experimental technique for carrying out such experiments is described, and its validity is demonstrated by showing that the results obtained from deforming an elastically isotropic olivine + magnesiowüstite sample agree, to within very tight bounds, with the behaviour predicted by theory for elastically isotropic composites.

Integration of Electrografted Layers for the Metallization of Deep TSVs

2010 ◽  
Vol 7 (3) ◽  
pp. 119-124
Author(s):  
F. Raynal ◽  
V. Mevellec ◽  
N. Frederich ◽  
D. Suhr ◽  
I. Bispo ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shelf Life ◽  
Design Space ◽  
Complete Characterization ◽  
Monitoring Strategy ◽  
Ic Design ◽  
Preliminary Results ◽  
Wide Range ◽  
Readiness Level

This paper describes production-readiness level of electrografted (eG) and chemical grafted (cG) layers deposited on a wide range of through silicon via (TSV) dimensions. Three layers are required to achieve via metallization: eG insulator, cG barrier, and eG copper seed. Complete characterization of each layer of the stack has been achieved, including electrical and mechanical properties. Impact on the 3D-IC design space of the electrografting nanotechnology optimized for highly conformal growth of TSV films is discussed. Four chemical baths are required to achieve the deposition of the three layers, shelf life, and bath monitoring strategy of each chemistry being presented in the last part of the paper. Some preliminary results of copper plating directly on top of the cG barrier are also reported.

scholarly journals Geomechanical characterization of lateritic hardpans from Bamendjou (West-Cameroon)

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Y. Ngueumdjo ◽  
V. H. Njuikom Djoumbi ◽  
V. Y. Katte ◽  
F. Ngapgue ◽  
A. S. L. Wouatong
Keyword(s):  
Mechanical Properties ◽  
Specific Gravity ◽  
Physical And Mechanical Properties ◽  
Western Region ◽  
Geochemical Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Geomechanical Characterization

AbstractThis study reports on the physical, mechanical, mineralogical and geochemical analysis carried out on four lateritic hardpan specimens from quarries in the Bamendjou area in the Western Region of Cameroon using common prescribed procedures. The results indicate that values of the bulk density, specific gravity, total and open porosities are very variable from one specimen to another. Meanwhile, the value of the compressive strengths of both the dry and immersed specimens were also very variable from one specimen to another, with the F2 and F1 specimens having higher values than the A1 and A2 specimens. All the specimens immersed in water recorded lower compressive strengths than the dry specimens. The flexural strengths also varied from one sample to another, with the F2 specimen having the highest resistance. The X-ray diffraction patterns reveal that the major peaks were assigned to gibbsite, goethite, and hematite, while the minor peaks were assigned to kaolinite and anatase. The mineralogy and geochemistry influenced the physical and mechanical properties, with the iron rich specimens having higher values in both the physical and mechanical properties than the alumina rich specimens. The results of the compressive strengths obtained were higher than (1–4) MPa obtained in Burkina Faso and India where they have been using latertic blocks for construction. Thus the hardpans of Bamendjou can also be exploited for building purposes conveniently.

scholarly journals Synthesis and Characterization of Polysulfone (PSU)/Philippine Halloysite (PH-HAL) Nanostructured Membrane via Electrospinning

2018 ◽  
Vol 213 ◽  
pp. 03001 ◽  
Author(s):  
Ruth R. Aquino ◽  
Marvin S. Tolentino ◽  
Niel Karl G. Arcamo ◽  
John Patrick N. Gara ◽  
Blessie A. Basilia
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Fibrous Composite ◽  
Polymeric Materials ◽  
Composite Membranes ◽  
Electrospinning Process ◽  
Synthesis And Characterization ◽  
Separation Processes ◽  
Wide Range

Membrane technology is widely used in many separation processes because of its multi-disciplinary characteristics. One of the techniques that is used in the fabrication of membranes is the electrospinning process which can create nanofibers from a very wide range of polymeric materials. In this study, electrospun nanostructured fibrous composite membranes of polysulfone (PSU), commercial halloysite (COM-HAL), and Philippine halloysite (PH-HAL) were synthesized. The concentrations of COM-HAL and PH-HAL were both varied from 0.5%, 1%, and 2%. The FTIR results showed that there were changes in the intensity of the PSU-IR spectra which confirmed the presence of COM-HAL and PH-HAL in the synthesized membranes. The SEM revealed that nanofibers can be successfully produced by the addition of LiCl salt in PSU with varying HAL concentrations. Also, it was observed that the addition of HAL with varying concentrations have no significant effect on wettability due to the strong hydrophobic character of the PSU membrane. Moreover, it was found from the analysis of mechanical properties that the tensile strength of the membranes weakened by the addition of HAL due to its weak interaction with PSU.

Processing and Characterization of Pure Nickel Sheets by Constrained Groove Pressing (CGP) Technique

2010 ◽  
Vol 667-669 ◽  
pp. 523-528 ◽  
Author(s):  
S.S.Satheesh Kumar ◽  
T. Raghu
Keyword(s):  
Mechanical Properties ◽  
Grain Refinement ◽  
Room Temperature ◽  
Considerable Increase ◽  
Vickers Microhardness ◽  
Deformation Behaviour ◽  
Pure Nickel ◽  
Size Evolution ◽  
Strain Magnitude

Pure nickel sheets are severe plastically deformed by constrained groove pressing technique at room temperature up to three passes. A total strain magnitude of 3.48 is imparted to the sheets and further processing is limited by initiation of surface microcracks. The grain size evolution studied by optical microscopy reveals significant grain refinement at the end of third pass evidently illustrating the effectiveness of groove pressing technique for grain refinement in sheet materials. Vickers microhardness measured during different stages of groove pressing process clearly describes the deformation behaviour in different segments of slant and flat regions. The change in mechanical properties of constrained groove pressed sheet is evaluated by room temperature tensile and microhardness tests. Results showed considerable increase in strength and hardness during initial passes followed by slight drop during third pass.

Processing and Characterization of Al2O3-YAG Composite

2012 ◽  
Vol 727-728 ◽  
pp. 1334-1339
Author(s):  
E.S. Lima ◽  
Luis Henrique Leme Louro ◽  
José Brant de Campos ◽  
R.R. de Avillez ◽  
Sérgio Neves Monteiro ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Phase Transition ◽  
Elevated Temperatures ◽  
Eutectic Reaction ◽  
Ceramic Matrix ◽  
Oxide Ceramics ◽  
High Temperature Mechanical Properties ◽  
Wide Range ◽  
Potential Use

Oxide ceramics show better oxidation resistance at high temperatures than other ceramics; however they are more susceptible to plastic deformation at elevated temperatures [. If their high temperature mechanical properties could be improved, they would be expected to open a wide range of applications as structural material [2, 3]. Several studies have revealed [4, 5] the potential use of YAG oxides as reinforcing component oxide in a ceramic matrix. Both YAG and Al2O3 have similar thermal expansion coefficient and they are chemically stable because of their low O2 vapor pressure. In addition, there is no solid state phase transition as the temperature rises, but the eutectic reaction at 1826°C with Al2O3 molar concentration of 81.5% and 18.5% for Y2O3 which enable a fusion processing, turning the Al2O3-YAG composites very attractive. This eutectic reaction is possible in the restrictive composition from 18.5 to 20.5 mol% Y2O3 [6].

scholarly journals Flexible and High Thermal Conductivity Composites Based on Graphite Nanoplates Paper Impregnated with Polydimethylsiloxane

2021 ◽  
Vol 5 (12) ◽  
pp. 309
Author(s):  
Daniele Battegazzore ◽  
Erica Fadda ◽  
Alberto Fina
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Deposition Time ◽  
Electronic Devices ◽  
Composite Films ◽  
Thermal And Mechanical Properties ◽  
Wide Range ◽  
High Flexibility ◽  
Highly Porous

This paper deals with the design, preparation, and characterization of conductive and flexible nanopapers based on graphite nanoplates (GNP) and polydimethylsiloxane (PDMS). Highly porous GNP nanopapers were first prepared by filtration from a GNP suspension in a solvent. Subsequently, PDMS impregnation was carried out to obtain a composite material. By varying the concentration of the polymer solution and the deposition time, PDMS/GNP nanopapers were produced with a wide range of PDMS contents, porosities, and densities. Thermal diffusivity of the composite films (both in-plane and cross-plane) were measured and correlated with the structure of the nanopapers. Selected formulations were investigated in detail for their physical, thermal, and mechanical properties, exhibiting high flexibility and resistance to more than 50 repeated bendings, stiffness of up to 1.3 MPa, and thermal conductivity of up to 25 W/m∙K. Based on the properties obtained, the materials presented in this paper may find applications in modern lightweight and flexible electronic devices.

scholarly journals High-throughput microfluidic characterization of erythrocyte shape and mechanical variability

2018 ◽  
Author(s):  
Felix Reichel ◽  
Johannes Mauer ◽  
Ahmad Ahsan Nawaz ◽  
Gerhard Gompper ◽  
Jochen Guck ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Red Blood Cells ◽  
High Throughput ◽  
Blood Cells ◽  
Microvascular Blood Flow ◽  
Flow Conditions ◽  
Wide Range ◽  
Single Well ◽  
Good Agreement

The motion of red blood cells (RBCs) in microchannels is important for microvascular blood flow and biomedical applications such as blood analysis in microfluidics. The current understanding of the complexity of RBC shapes and dynamics in microchannels is mainly based on several simulation studies, but there are a few systematic experimental investigations. Here, we present a combined study, which systematically characterizes RBC behavior for a wide range of flow rates and channel sizes. Even though simulations and experiments generally show good agreement, experimental observations demonstrate that there is no single well-defined RBC state for fixed flow conditions, but rather a broad distribution of states. This result can be attributed to the inherent variability in RBC mechanical properties, which is confirmed by a model that takes the variation in RBC shear elasticity into account. This represents a significant step toward a quantitative connection between RBC behavior in microfluidic devices and their mechanical properties, which is essential for a high-throughput characterization of diseased cells.Significance StatementThe ability to change shape is crucial for the proper functioning of red blood cells under harsh conditions in the microvasculature, since their shapes strongly affect the flow behavior of whole blood. Our results from simulations and systematic experiments reveal the shapes and dynamics of red blood cells for different flow conditions and channel dimensions, generally in good agreement. However, in the experiments, cells do not exhibit a single well-defined shape for fixed flow conditions. We show that this distribution of shapes can be attributed to the variability in mechanical properties of red blood cells.

scholarly journals Structure and mechanical properties of Octopus vulgaris suckers

2014 ◽  
Vol 11 (91) ◽  
pp. 20130816 ◽  
Author(s):  
Francesca Tramacere ◽  
Alexander Kovalev ◽  
Thomas Kleinteich ◽  
Stanislav N. Gorb ◽  
Barbara Mazzolai
Keyword(s):  
Mechanical Properties ◽  
Soft Robotics ◽  
Octopus Vulgaris ◽  
Viscoelastic Parameters ◽  
Artificial Materials ◽  
Wide Range ◽  
The Common ◽  
New Generation ◽  
Attachment Process

In this study, we investigate the morphology and mechanical features of Octopus vulgaris suckers, which may serve as a model for the creation of a new generation of attachment devices. Octopus suckers attach to a wide range of substrates in wet conditions, including rough surfaces. This amazing feature is made possible by the sucker's tissues, which are pliable to the substrate profile. Previous studies have described a peculiar internal structure that plays a fundamental role in the attachment and detachment processes of the sucker. In this work, we present a mechanical characterization of the tissues involved in the attachment process, which was performed using microindentation tests. We evaluated the elasticity modulus and viscoelastic parameters of the natural tissues ( E ∼ 10 kPa) and measured the mechanical properties of some artificial materials that have previously been used in soft robotics. Such a comparison of biological prototypes and artificial material that mimics octopus-sucker tissue is crucial for the design of innovative artificial suction cups for use in wet environments. We conclude that the properties of the common elastomers that are generally used in soft robotics are quite dissimilar to the properties of biological suckers.

Biological and mechanical evaluation of mineralized-hydrogel scaffolds for tissue engineering applications

2021 ◽  
pp. 088532822199542
Author(s):  
Aitor Tejo-Otero ◽  
Alastair C Ritchie
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Biological Properties ◽  
Hydrogel Scaffolds ◽  
Wide Range ◽  
Calcium Minerals ◽  
The One ◽  
Calcium Compounds ◽  
Cell Adhesion And Proliferation

Chitosan and gelatin have been extensively used in tissue engineering for a wide range of different applications, such as wound healing or bone regeneration, due to their advantages: excellent biocompatibility (promoting cell adhesion and proliferation), low price and biodegradability. Nonetheless, their main drawback is that they have poor mechanical properties, consequently restricting their use in bone tissue engineering. In previous studies, both materials were cross-linked, with added calcium minerals, which led to an improvement in both mechanical and biological properties. Therefore, this study carries out a mechanical and biological characterization of mineral-hydrogel scaffolds in order to find the best compositions. Different proportions of calcium compounds (CaCO3 and CaHPO4) are used to make up between 20% and 30% of the minerals used in a mineral-hydrogel mix. This addition of minerals enhances not only the mechanical properties, but also the biological ones. On the one hand, the higher the amount of minerals added to the composition, the better the mechanical properties obtained. Additionally, as the proportion of CaCO3 in comparison with CaHPO4 rises, the mechanical properties improve. On the other hand, both cell proliferation and mineralization are improved with the addition of calcium minerals.

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