Rate Dependency and Stress Relaxation of Unsaturated Clays

The specimens (980 MPa-grade dual phase steel sheets) were stretched until the pre-defined strain was obtained. Then the specimens were held at the pre-defined strain and measured the change of stress durng holding. We investigated the effects of strain rate and strain at the starting time of holding and whether the stress change during holding could be described by Krempl model. The following results were obtained. First, the stress drop increased with increase of strain rate and the holding time. On the other hand, the stress drop was not affected by strain change at the starting time of holding. Second, initial stress relaxation rate increased with increase of strain rate. However, this strain rate dependency to stress relaxation rate diminished as the holding time became long enough roughly more than 100 s. Third, the stress change during holding obtained by Krempl model accurately agreed with experimental result. It was found that the stress change during holding could be well described by using Krempl model. This suggests that dislocation moves viscously. In addition, the strain rate dependency on stress change during holding could be described by change of the parameter A.

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Stress Relaxation and the Formation of Silicides in the Process of the Crystallization of NI-NB Films on SI

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088804 ◽

1991 ◽

Vol 49 ◽

pp. 898-899

Author(s):

N. Rozhanski ◽

V. Lifshitz

Keyword(s):

Thin Films ◽

Stress Relaxation ◽

Integrated Circuits ◽

Direct Evidence ◽

Alloy Film ◽

Diffusion Barriers ◽

Effective Barrier

Thin films of amorphous Ni-Nb alloys are of interest since they can be used as diffusion barriers for integrated circuits on Si. A native SiO2 layer is an effective barrier for Ni diffusion but it deformation during the crystallization of the alloy film lead to the appearence of diffusion fluxes through it and the following formation of silicides. This study concerns the direct evidence of the action of stresses in the process of the crystallization of Ni-Nb films on Si and the structure of forming NiSi2 islands.

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Supplemental Material for BDNF Val66Met Polymorphism to Generalized Anxiety Disorder Pathways: Indirect Effects via Attenuated Parasympathetic Stress-Relaxation Reactivity

Journal of Abnormal Psychology ◽

10.1037/abn0000507.supp ◽

2020 ◽

Keyword(s):

Anxiety Disorder ◽

Stress Relaxation ◽

Generalized Anxiety Disorder ◽

Indirect Effects ◽

Generalized Anxiety ◽

Val66met Polymorphism ◽

Bdnf Val66met Polymorphism

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BDNF Val⁶⁶Met polymorphism to generalized anxiety disorder pathways: Indirect effects via attenuated parasympathetic stress-relaxation reactivity.

Journal of Abnormal Psychology ◽

10.1037/abn0000507 ◽

2020 ◽

Vol 129 (3) ◽

pp. 237-247 ◽

Cited By ~ 2

Author(s):

Hsin-An Chang ◽

Wen-Hui Fang ◽

Yia-Ping Liu ◽

Nian-Sheng Tzeng ◽

Jia-Fwu Shyu ◽

...

Keyword(s):

Anxiety Disorder ◽

Stress Relaxation ◽

Generalized Anxiety Disorder ◽

Indirect Effects ◽

Generalized Anxiety

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STRESS RELAXATION IN SOLIDS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1987801 ◽

1987 ◽

Vol 48 (C8) ◽

pp. C8-3-C8-13 ◽

Cited By ~ 1

Author(s):

J. KUBÁT ◽

M. RIGDAHL

Keyword(s):

Stress Relaxation

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Comparative study of the effective parameters on residual stress relaxation in welded aluminum plates under cyclic loading

Mechanics & Industry ◽

10.1051/meca/2020061 ◽

2020 ◽

Vol 21 (5) ◽

pp. 505

Author(s):

Yousef Ghaderi Dehkordi ◽

Ali Pourkamali Anaraki ◽

Amir Reza Shahani

Keyword(s):

Residual Stress ◽

Cyclic Loading ◽

Stress Relaxation ◽

Stress Amplitude ◽

Cyclic Plasticity ◽

Mean Stress ◽

Effective Parameters ◽

Perfect Plasticity ◽

Residual Stress Relaxation ◽

Aluminum Plates

The prediction of residual stress relaxation is essential to assess the safety of welded components. This paper aims to study the influence of various effective parameters on residual stress relaxation under cyclic loading. In this regard, a 3D finite element modeling is performed to determine the residual stress in welded aluminum plates. The accuracy of this analysis is verified through experiment. To study the plasticity effect on stress relaxation, two plasticity models are implemented: perfect plasticity and combined isotropic-kinematic hardening. Hence, cyclic plasticity characterization of the material is specified by low cycle fatigue tests. It is found that the perfect plasticity leads to greater stress relaxation. In order to propose an accurate model to compute the residual stress relaxation, the Taguchi L18 array with four 3-level factors and one 6-level is employed. Using statistical analysis, the order of factors based on their effect on stress relaxation is determined as mean stress, stress amplitude, initial residual stress, and number of cycles. In addition, the stress relaxation increases with an increase in mean stress and stress amplitude.

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