An electronic device integrates diverse materials, and inevitably contains sharp features, such as interfaces and corners. When the device is subject to thermal and mechanical loads, the corners develop intense stress and are vulnerable sites to initiate failure. This paper analyzes stress fields at corners in flip-chip packages. The stress at a corner is a linear superposition of two modes of ...

To identify mechanical properties in heterogeneous materials, the local stress fields have to be estimated. The recent developments in imaging techniques allow reaching precise and spatially dense kinematic fields (e.g. displacement, strain ...). In this paper, an iterative procedure is used to identify the distribution of elastoplastic material parameters and the local stress fields. The formu...

Dry, frictional, steady-state granular flows down an inclined, rough surface are studied with discrete particle simulations. From this exemplary flow situation, macroscopic fields, consistent with the conservation laws of continuum theory, are obtained from microscopic data by time-averaging and spatial smoothing (coarse-graining). Two distinct coarse-graining length scale ranges are identified...

In this research, the effects of electromagnetic fields of various strengths (0, 1 and 2mT) have been investigated on antioxidant enzymes activity in Valerian (Valeriana officinalis L.). The dry and wet (soaked for 30 min) Valerian seeds were exposed to electromagnetic fields 30 min per day for 3 days. Each treatment and control groups had 3 replicates and 10 seeds were employed for each replic...

• Clarification of stress intensity factor superposition under crack closure phenomena. Importance geometry changes by for is demonstrated. Proposal and discussion two alternative residual applied definitions. Discussion face contact modelling calculation in fatigue load cycles. The correlation between (SIF) range growth a powerful tool fail-safe design approaches to lightweight structures. key...

*Correspondence: Shigekazu Kusumoto, Graduate School of Science and Engineering for Research, University of Toyama, 3190 Gofuku, Toyama-shi, Toyama 930-8555, Japan e-mail: [email protected] Many rock fractures are entirely driven open by fluids such as ground water, geothermal water, gas, oil, and magma. These are a subset of extension fractures (mode I cracks; e.g., dikes, mineral veins ...

In this article, the anti-plane deformation of an orthotropic sector with multiple defects is studied analytically. The solution of a Volterra-type screw dislocation problem in a sector is first obtained by means of a finite Fourier cosine transform. The closed form solution is then derived for displacement and stress fields over the sector domain. Next, the distributed dislocation method is em...

In this article, the magneto-thermo-elastic problem of exponentially graded material (EGM) hollow rotating disk placed in uniform magnetic and temperature fields is considered. Exact solutions for stresses and perturbations of the magnetic field vector in EGM hollow rotating disk are determined using the infinitesimal theory of magneto-thermo-elasticity under plane stress. The material properti...