摘要:

The aim of this study is a two-dimensional transient analysis of the electron-beam welding process. This simulation is based on the finite element method to calculate temperature, metallurgical proportions, stresses, and strains in a transient analysis for welding of thick steel pieces.

ISSN:0149-5739    

DOI:10.1080/01495739608946171

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In this study an unconstrained elastic layer under statically self-equilibrating thermal or residual stresses is considered. The layer is assumed to be a functionally graded material (FGM), meaning that its thermo-mechanical properties are assumed to be continuous functions of the thickness coordinate. The layer contains an embedded or a surface crack perpendicular to its boundaries. Using superposition the problem is reduced to a perturbation problem in which the crack surface tractions are the only external forces. The dimensions, geometry, and loading conditions of the original problem are such that the perturbation problem may be approximated by a plane strain mode I crack problem for an infinite layer. After a general discussion of the thermal stress problem, the crack problem in the nonhomogeneous medium is formulated. With the application to graded coatings and interfacial zones in mind, the thickness variation of the thermo-mechanical properties is assumed to be monotonous. Thus, the functions such as Young's modulus, the thermal expansion coefficient, and thermal conductivity may be expressed by appropriate exponential functions through a two-parameter curve fit. The crack problem is reduced to an integral equation with a generalized Cauchy kernel and solved numerically. After giving some sample results regarding the distribution of thermal stresses, stress intensity factors for embedded and surface cracks are presented. Also included are the results for a crack / contact problem in a FGM layer that is under compression near and at the surface and tension in the interior region.

ISSN:0149-5739    

DOI:10.1080/01495739608946172

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In the context of the linear theory of thermoelasticity without energy dissipation for homogeneous and isotropic materials, an initial boundary value problem in terms of stress and entropy-flux is formulated and the uniqueness of its solution established.

ISSN:0149-5739    

DOI:10.1080/01495739608946173

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The boundary element method (BEM) does not require a domain integral in steady thermoelastic problems without heat generation. However, in problems with heat generation, the domain integral is necessary. This article shows that the axisymmetric problem of steady thermoelasticity with nonuniform heat generation over the region can be easily solved without a domain integral by means of BEM. This method can also be applied to steady thermal stress problems under complicated general heat generation. However, for general heat generation the domain must be divided into small areas in which distributions of the heat generation approximately satisfy the Laplace equation.

ISSN:0149-5739    

DOI:10.1080/01495739608946174

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Exact analytical solutions are given for stationary two-dimensional temperature, stress, and displacement distributions in hybrid laminates containing isotropic and/or orthotropic layers. The similarity that exists between the thermoelastic and piezoelastic formulations is exploited in establishing solutions for cylindrical bending of piezother-moelastic laminates exposed to combined thermo-electro-mechanical loads. Results are compared with those based upon classical and high-order bending theories.

ISSN:0149-5739    

DOI:10.1080/01495739608946175

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:0149-5739    

DOI:10.1080/01495739608946176

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor