This paper studies the elastic contact in filaments induced by surface adhesion, which plays an important role in the mechanical response of fibrous materials (e.g., fiber friction, sliding, compression hysteresis, etc.). During the process, a simple 3D elastic contact model was proposed. The filaments were assumed to be uniform, smooth elastic cylinders, and the adhesive force between filament...

BACKGROUND Strain rate (SR) imaging (SRI) is a tissue Doppler-based method of regional myocardial deformation imaging. The aim of this study was to see whether SRI could quantify changes in myocardial mechanical function after an acute myocardial infarction, and to follow the time course of these changes. METHODS In all, 26 consecutive patients with first-time acute myocardial infarctions wer...

At room temperature, plastic flow of metallic glasses (MGs) is sharply localized in shear bands, which are a key feature of the plastic deformation in MGs. Despite their clear importance and decades of study, the conditions for formation of shear bands, their structural evolution and multiplication mechanism are still under debate. In this work, we investigate the local conditions at shear band...

In 1985, 1987 and 1988, we measured deformation of bore holes in the ablation zone of Storglaciaren. A different hole was used each year. Deformation profiles were determined for four consecutive time periods between mid-July and early September. All three holes were in an area where the glacier lies in an overdeepened part of the bed, up-glacier from a riegel. The first hole was approximately ...

We study the impact of strain localization on the stability of frictional slipping in dense amorphous materials. We model the material using shear transformation zone (STZ) theory, a continuum approximation for plastic deformation in amorphous solids. In the STZ model, the internal state is quantified by an effective disorder temperature, and the effective temperature dynamics capture the spont...

An empirical method of non-destructive testing of a material was developed using pulse transmission by acoustic emission transducers to determine plastic deformation of 304 stainless steel specimens. This was done by means of comparison of pulse signals detected in an undeformed section with the pulse signals detected after passing through the deformation zone in the specimens. The pulse signal...

Deformation in the Earth is rarely homogeneous and often occurs in narrow regions of concentrated strain referred to as zones of shear localization. Mylonites found in the continental crust are the manifestation of shear localization (White et al. 1980) and, at the largest scale, shear localization is proposed to be crucial for the generation of tectonic plates from a convecting mantle (Bercovi...

This paper presents results from a research initiative aimed at investigating high temperature creep deformation mechanisms in Ni-base superalloys through a combination of creep experiments, TEM deformation mechanism characterization, and state of the art modeling techniques. The effect of microstructure on dictating creep rate controlling deformation mechanisms was revealed for specimens with ...

We use considerations of energy balance and dissipation to derive a self-consistent version of the shear-transformation-zone (STZ) theory of plastic deformation in amorphous solids. The theory is generalized to include arbitrary spatial orientations of STZs. Continuum equations for elasto-plastic material and their energy balance properties are discussed.

In this work, a finite-element model was elaborated to simulate the thermomechanical behavior of 6061 aluminum alloy during friction-stir welding (FSW). It shown that FSW-induced deformation is two-stage process. addition stirring action exerted by rotating tool probe, material in near-surface area stir zone also experienced secondary shoulder edge after passage tool. Both steps were found be c...