Stress Intensity Of Debonding Research Articles

Bimaterial infinite plane with a cavity on the interface subjected to different temperatures

Stress analysis is applied to two bonded materials of infinite extent with a single notch at their interface. The two materials, represented in normal view as two joined half planes with a notch, are subjected to different temperatures. As illustration, a bimaterial infinite plane with an elliptical hole at the interface is analyzed. To achieve a closed-form solution, a rational mapping function and a complex variable method are used. By changing the mapping function, other geometries for the notch can be analyzed. The cavity at the interface constitutes a small defect because its extent is small compared with the infinite plane. A mathematical difficulty arises with the presence of the points at infinity of the half planes. The coefficients of the homogeneous part of the stress function are expressible in terms of Dundurs’ parameters, but the temperature-dependent loading term is not. Stress distributions without and with debonding for two pairings of bimaterial are shown. The stress intensity of debonding is defined, and values are investigated for various debonding lengths for the elliptical holes. Also the debonding extension is investigated. As a special case, the stress intensity factors for T-shaped cracks are also investigated.

Solution of a bonded bimaterial problem of two interfaces subjected to different temperatures

A closed-form solution is derived for the bonded bimaterial planes at two interfaces subjected to different temperatures. The bonded planes with two interfaces are symmetric with respect to the interface, which is straight. A rational mapping function and complex stress functions are used for the analysis. The problem is reduced to a Riemann–Hilbert problem. The solution includes an integral term. This integral cannot be carried out. However, the first derivative of complex stress functions which does not include integral terms with regard to the variables of the mapping plane is achieved. Therefore, there is no need for numerical integration to calculate stress components and to determine unknown coefficients in a complex stress function. This is very beneficial. It is more difficult to derive the solution to the two-interface problem compared to the general solution. As a demonstration of geometry, semi-strips bonded in two places at the ends of strips are considered. Unbonded parts are a model of debonding. The solution for different geometrical shapes can be obtained by changing the mapping function. Some stress distributions are shown for different lengths of the interface. The stress intensity of debonding (SID) (corresponding to the root of strain energy release rate) is investigated for the debonding extension. SID is the same as the root of strain energy release rate for the evaluation of the strength at the debonding tip.

Solution of problem of two dissimilar materials bonded at one interface subjected to temperature

A solution of problem of two dissimilar materials bonded at one interface subjected to temperature is derived. To obtain a closed-form solution, a rational mapping function and a complex variable method are used. The coefficients of the homogeneous part of the stress function are expressed by Dunders’ parameters, but loading term of temperature is not expressed by them. As a demonstration, semi-strips bonded at one part at the ends are considered. The each strip is subjected to uniform temperature. Examples of stress distributions are shown. The relations of stress and temperature on the interface are described. Debondings on both sides of the interface are considered. Stress intensity of debonding (SID) is defined, and the values are investigated for various debonding lengths. And the debonding extension or the crack initiation into the material is investigated. The effects of material constants (Dundurs’ parameter) on SID are also investigated. By changing mapping function, other geometries can be analyzed.

Thin plate bending of dissimilar half-planes with interface debonding emanating from an elliptical hole

The problem of thin plate bending of two bonded dissimilar half-planes containing an elliptical hole on the interface with debonding emanating on both sides is presented. The external load is a uniformly distributed bending moment applied at infinity perpendicular to the interface. An analytical solution is obtained using the complex stress function approach and the rational mapping function technique. Stress distributions on the interface, the boundaries of the hole and in the vicinity of the debonded tips are obtained. The stress intensity of debonding is obtained for aribitrary lengths of debonding, all possible hole dimensions and rigidity ratios.

Stress Analysis of Bimaterial Strip with Debondings under Tension

A bimaterial problem of strips which are bonded at their ends is solved. The bonded part is one part and debondings occur on both sides of the interface. The debonding lengths are changed, and concentrated loads are applied at the tips of each strip. The complex variable method and a rational mapping function are used for the analysis. Stress distributions are shown for two different locations of the interface. Stress intensity of debonding is defined and the values are obtained for various debonding lengths. Debonding and the effect of material constants on debonding are also investigated.

Thin plate bending problem of dissimilar strips with two bond lines

A solution to the thin plate bending problem of partially bonded dissimilar strips with two bond lines is presented. The two strips are symmetrically bonded with respect to the interface which is on theX-axis. The complex stress functions approach together with the rational mapping function technique are used in the analysis. A concentrated bending moment applied at each strip is considered. Distributions of bending and torsional moments, as well as the stress intensity of debonding (SID) at the debonding tips are obtained, and the debonding extension is investigated.

Bimaterial plane with elliptic hole under uniform tension normal to the interface

A bimaterial plane subject to uniform tensile traction normal to the interface is analyzed. The plane consists of two dissimilar elastic half-planes each with a semi-elliptic notch. The stress analysis is carried out by using a rational mapping function and complex stress ones. Stress Intensity of Debonding is defined as an index for the stress intensity at the tip of debonding and is investigated. The expression of energy release rate is derived by applying the residue theorem to a contour integral expressed by the complex stress function. Stress distributions around a circular hole and on the interface are shown. Stress concentration factors are studied for various oval shapes, material constants, and debonding lengths. Expressions of stress concentration factor are given.

Thin plate bending problem of partially bonded bi-material strips

A general solution to the thin plate bending problem of partially bonded bi-material strips is obtained. The two strips are symmetrically bonded along a finite straight interface with debondings at both sides. Complex stress function approach together with the rational mapping function technique are utilized to obtain the general solution. A concentrated bending moment applied at eachtip of the strip is considered. Distributions of bending and torsional moments along the boundaries of the two strips as well as the Stress Intensity of Debonding (SID) at the debonding tips are demonstrated for different states of debonding lengths, material constants and rigidity ratios.

集中偶力を受ける異材半無限板接合端に発生したクラックおよびはく離

The stress states of partially bonded bi-material half planes with an edge crack under couples at infinity were analyzed by using a rational mapping function and complex stress functions. Stress distribution and stress intensity factors were obtained. Stress intensity of debonding was related to the energy release rate, and re-extension of debonding after crack initiation was discussed.