I nstrumented indentation testing (IIT) is a technique for measuring the mechanical properties of materials. It is a development of traditional hardness tests such as Brinell, Rockwell, Vickers, and Knoop. IIT is similar to traditional hardness testing in that a hard indenter, usually diamond, is pressed into contact with the test material. However, traditional hardness testing yields only one ...

BIFURCATIONS, including shear band and diffuse geometric modes, arc analysed for plane strain deformation of a rectangular slab subject to a constant lateral confining stress. The response of the slab material is characterized by an incrementally linear constitutive relation that allows for the possibility of volume change accompanying shear deformation, pressure dependence and deviations from ...

The elastic modulus of cellulose Ib in the axial and transverse directions was obtained from atomistic simulations using both the standard uniform deformation approach and a complementary approach based on nanoscale indentation. This allowed comparisons between the methods and closer connectivity to experimental measurement techniques. A reactive force field was used that explicitly describes h...

The mechanical response of a homogeneous isotropic linearly elastic material can be fully characterised by two physical constants, the Young’s modulus and the Poisson’s ratio, which can be derived by simple tensile experiments. Any other linear elastic parameter can be obtained from these two constants. In contrast, the physical responses of nonlinear elastic materials are generally described b...

Ultrasound elastography could be used as a new noninvasive technique for detecting early osteoarthritis. As the first critical step, this study theoretically predicted the excitation power and the measurement errors in detecting cartilage detect. A finite element model was used to simulate wave propagation of elastography in the cartilage. The wave was produced by a force F, and the wave speed ...

The paper presents a FE-analysis of a spontaneous shear localization inside non-cohesive sand during plane strain compression. The calculations were carried out with a gradient-enhanced hypoplastic constitutive law. The hypoplastic law can reproduce essential features of granular bodies depending on the void ratio, pressure level and deformation direction. To model the thickness of shear zones,...

AIMS Monocytes play a significant role in the development of atherosclerosis. During the process of inflammation, circulating monocytes become activated in the blood stream. The consequent interactions of the activated monocytes with the blood flow and endothelial cells result in reorganization of cytoskeletal proteins, in particular of the microfilament structure, and concomitant changes in ce...

The mechanical properties of free-standing electron beam deposited amorphous carbon structures have been studied using atomic force microscopy. The fabricated carbon blades are found to be extraordinarily flexible, capable of undergoing vertical deflection up to ∼ 75% of their total length without inelastic deformation. The elastic bending modulus of these structures was calculated to be 28 ± 1...

We report the synthesis of a three-dimensional (3D) macroassembly of graphene sheets with electrical conductivity (∼10(2) S m(-1)) and Young's modulus (∼50 MPa) orders of magnitude higher than those previously reported, super-compressive deformation behavior (∼60% failure strain), and surface areas (>1300 m(2) g(-1)) approaching theoretically maximum values.