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The finite element method (FEM) is used daily in the automotive industry for such purposes as reducing the time of product development and improving the design based on analysis results, followed by later validation by tests in the laboratory and on the proving ground. This paper will present some of the methodology used to develop automotive components by finite element analysis, including procedures to specialize FEM models to obtain quantitative and qualitative results for systems such as body, chassis, and suspension components, as well as validation of the models by experimental data.

Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth and closure processes. Today structural and materials engineers develop structures and materials properties using this technique. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Keyhole Specimen Test Load Histories by finite element analysis. The crack propagation simulation was based on release nodes in the minimum loads to minimize convergence problems. To understand the crack propagation processes under variable amplitude loading, retardation effects are observed.

The present work presents the numerical determination of fatigue crack opening and closure stress intensity factors of a C(T) specimen under variable amplitude loading by finite element method. A half compact tension C(T) specimen, assuming plane stress constraint, was modeled by finite element method. The effects in two-dimensional (2D) small scale yielding models of fatigue crack growth under modified Mini-Falstaff spectrum loading were studied. The crack propagation model was based on release nodes in the minimum loads to minimize convergence problems. To understand the crack propagation processes under variable amplitude loading, retardations models were observed.

The objective of this paper is to provide a review of retardation models for constant and variable amplitude spectrum loading in 2D constrained small scale yielding. The models considered use a numerical 2D finite element method to determine crack opening and closing stress intensity factors. The correlation of the predictions of the models with experimental data is examined. Procedures used to edit variable amplitude spectrum loading are also presented and the effects of this editing on fatigue life predictions for structural components are discussed.

The present paper introduces a weld seam simulation in suspension components. Are modeled seven types weld seam in shock absorbers structures. Hypermesh and Abaqus are used as pre-postprocessor and solver respectively to perform the numerical models. An experimental test was conducted to validate the numerical results. The design criterion used in the finite element models are fatigue or 0.7 yield stress to rotative flexion load. The correlation between numerical and experimental data are closed and the best option of weld seam to be used regarding manufacture and stress level was selected. The option will released for production after fatigue laboratory tests.

The objective of this paper is to provide a review of work covering the effects of constraint in two-dimensional (2D) small scale yielding models of fatigue crack growth under constant and variable spectrum loading. It considers crack propagation and retardation models developed to understand crack propagation processes. The paper also treats numerical 2D finite element method models used to determine the crack opening and closure stress intensity factors. Also presented are procedures used to determine the crack opening and closure under variable amplitude loading.

The present paper will show a methodology to develop shock absorbers using finite element method. It will presented which components are involved in the model from shock absorber considered by finite element method. It is presented also the procedure to create the components as well as the types of elements, formulation, parameters of mesh quality, warpage factor as well as the others parameters necessary that, must to be use for a consistent numerical results when compared with experimental data. The boundary conditions used and the procedures to apply forces will shown too. CAS Brazil use Hypermesh for pre-postprocessor and ABAQUS for solver linear and nonlinear problems. Is presented an example of the methodology as well as the validation with experimental data.

The proposal of this paper is to review some crack closure models. Christensen discovered the crack closure in 1963, which was later defined by Elber in 1968. The first analytical crack closure model was developed by Newman in 1974, based on the Dugdale crack model. Since Newman, finite element and difference analysis have been conducted to obtain a basic understanding of crack growth and crack closure processes. Simple and complex models were developed based on the plasticity induced crack closure behavior. Since 1970 until today, the most finite elements analysis were conducted using two dimensional models under both, plane stress and plane strain conditions. In the literature, few works covering three-dimensional models can be found. Chermahini did the first work discussing it, in 1986. This paper also discusses the yielding zone, empirical crack closure model, modified Dugdale crack model and design concepts using short crack theory.