Showing papers on "Composite laminates published in 1970"
TL;DR: In this article, the response of a finite-width composite laminate under uniform axial strain is treated through the application of classical elasticity theory, and finite-difference solution techniques are employed to obtain solutions for stresses and displacements throughout the region.
Abstract: The response of a finite-width composite laminate under uniform axial strain is treated through the application of classical elasticity theory. Finite-difference solution techniques are employed to obtain solutions for stresses and displacements throughout the region. Results for material properties typical of a high modulus graphite-epoxy composite material system are presented which explain the mechanism of shear transfer within a symmetric laminate. In addition, results of this work are compared to those given in a recent approximate formulation.
1,048 citations
TL;DR: In this article, the exact solution of the problem of a pinned-end laminate composed of N layers, each of which possesses only a single plane of elastic symmetry, under cylindrical bending is investigated.
Abstract: Investigation of the success of classical lamination theory in predicting the response of composite laminates under static bending is extended by consideration of the influence of shear coupling. Specifically, we treat the exact solution of the problem of a pinned-end laminate composed of N layers, each of which possesses only a single plane of elastic symmetry, under cylindrical bending. Several example problems, involving unidirectional and angle-ply composites, are solved and the detailed results compared to corresponding approximate solutions. Some observations are offered in regard to the general range of validity of classical laminated plate theory.
245 citations
TL;DR: In this article, a review of the theoretical analysis of the mechanical and thermal properties of unidirectional fibrous composites is presented, focusing on the properties of composite thermal expansion coefficients and specific heats.
Abstract: Basic composite properties can be related to those of their constituents by available theoretical results which are, on the one hand, relatively simple, and yet which are representative of the actual physical response of the materials. The present paper reviews recent developments in the theoretical analysis of the mechanical and thermal properties of fibrous composites. Comparisons with available experimental results are presented. Attention is focused on the properties of unidirectional fibrous composites. The definition of effective composite properties and methods for the analysis of the elastic moduli of such composites are reviewed. Theoretical results for composite thermal expansion coefficients and specific heats are presented. Tensile strength studies based on statistical failure models are then described. Effects of variations in fibre strength and of non-uniform stress distributions are treated. Finite length fibres and uniform strength fibres are also considered. Emphasis is placed upon demonstrating that the influence upon composite strength of the statistical nature of the strength of contemporary advanced filaments is susceptible to rational analysis.
45 citations
TL;DR: In this paper, a statistical theory of material strength is proposed, where the strength of the elements is assumed to be a statistic a quantity, and as the material is loaded elements fracture randomly throughout the body causing localized stress concentrations.
35 citations
30 Aug 1970
TL;DR: In this article, a composite consisting of an aluminum alloy matrix and a graphite fiber reinforcement was developed with strengths exceeding the 'rule of mixture' strength of 101 ksi, which is not degraded by temperature to 550C or by thermal cycling from -193 to +500C.
Abstract: : A composite consisting of an aluminum alloy matrix and a graphite fiber reinforcement was developed with strengths exceeding the 'rule of mixture' strength of 101 ksi. The composite is not degraded by temperature to 550C or by thermal cycling from -193 to +500C. The importance of various processing techniques to the successful development of this composite and the effects of certain process variables on properties are discussed. (Author)
12 citations
DOI•
01 Jan 1970
TL;DR: In this paper, a formulation based on integral equations is proposed in order to analyse the edge-stress problem in composite laminates subjected to uniaxial extension, and the integral equations are obtained by employing a direct approach founded on the reciprocity theorem.
Abstract: A formulation based on integral equations is proposed in order to analyse the edge-stress problem in composite laminates subjected to uniaxial extension. The integral equations are obtained by employing a direct approach founded on the reciprocity theorem. Once the fundamental solutions are known, the proposed formulation allows a straightforward solution of the problem by the boundary element method. The enforcement of displacement and traction continuity along the interfaces leads to a set of linear algebraic equations providing the problem solution. Some numerical applications are presented and good agreement between the results obtained with the proposed method and the existing ones is shown. The stress singularity arising at the laminate free edges is investigated determining its power and strength.
9 citations
8 citations
2 citations
2 citations
01 Jan 1970
2 citations
Dissertation•
01 Jan 1970
TL;DR: In this article, the authors propose a method to solve the problem of space-time anomaly detection in the field of aeronautics and Astronautics, which is based on the M.S. Thesis.
Abstract: Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics. Thesis. 1970. M.S.
01 Jan 1970
TL;DR: Unidirectional fiber reinforced composites strength, obtaining limit load bounds from plasticity analysis, was obtained by as discussed by the authors, where the authors obtained a limit load bound from the plasticity of the composites.
Abstract: Unidirectional fiber reinforced composites strength, obtaining limit load bounds from plasticity analysis