Analysis of thermomechanical cyclic behavior of unidirectional metal matrix composites

Çöker, Demirkan
Nicholas, Theodore
An analytical tool is developed to determine the three-dimensional stress state in a unidirectional composite subjected to axial loading and changes in temperature. A finite difference method is used to analyze a representative volume element of the composite which consists of concentric cylinders. The constituents are assumed to be elastic-plastic materials having temperature dependent properties. An iterative technique using the Prandtl-Reuss flow rule to determine incremental plastic strains is implemented in a computer code capable of predicting the axisymmetric triaxial stresses in a composite under thermomechanical fatigue (TMF) loading conditions. The model is verified with finite element method calculations for the problem of thermal residual stresses resulting from cool-down from the processing temperature. Results for several TMF loading conditions are compared with experimental data and 1-D predictions for a SCS-6 silicon carbide fiber and Ti-24Al-11Nb matrix composite. Significant differences are noted between results based on 1-D and 3-D approximations to the stress state in a composite and are discussed in detail.


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Citation Formats
D. Çöker and T. Nicholas, “Analysis of thermomechanical cyclic behavior of unidirectional metal matrix composites,” San Diego, California, Amerika Birleşik Devletleri, 1993, p. 50, Accessed: 00, 2021. [Online]. Available: