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The aluminium composite foams reinforced by different volume fractions of SiC particles were manufactured with the direct foaming route of melt using different contents of CaCO3 foaming agent. The density of produced foams changed from 0·43 to 0·76 g cm−3. The microstructural features and compressive properties of the Al/SiCp composite foams were investigated. Compressive stress–strain curve of Al/SiCp composite foams is not smooth and exhibits some serrations. At the same relative density of composite foams, the plateau stress of the composite foams increases with increasing volume fraction of SiCp and decreasing weight percentage of CaCO3. The relation between plateau stress, relative density, weight percentage of CaCO3 and SiCp volume fraction of Al/SiCp composite foams with a given particle size was investigated.

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Based on the small deformation theory and Tresca's yield criterion an axisymmetric, plane strain, elastoplastic, thermal stress analysis for a cylindrical vessel made of functionally graded elastic, perfectly plastic material is offered. Elastic modulus and yield strength coefficients are assumed to be power functions of radius and linear functions of temperature. A cylindrical vessel is taken to be composed of two or more nested fully elastic and perfectly plastic cylinders. By comparing the values of the deformation or stress components in the interfaces of the neighboring cylinders, a system of equations is formed. The interfacial boundary values of the fully elastic or perfectly plastic regions are obtained by simultaneous solution of the resulting interfacial consistency conditions. Having prepared the closed form solutions for the stress fields in purely elastic and purely plastic regions, the distribution of stress throughout the vessel can be obtained. Using this model, in some sample problems, the influences of temperature and pressure on the stress, strain, and plastic zone patterns are studied. The location of plastic zones is obtained for a class of material property compositions.

Generally, in functionally graded material structures, a ceramic material as reinforcing part is distributed in a metallic matrix. These structures benefit the merits of both their metallic and ceramic parts such as the mechanical strength and thermal resistance. An important aspect in the function and study of functionally graded material structures is the effect of temperature. Usually, the resulted thermal stresses are so high that partial failure of structure is inevitable. In this paper, by using of different exact and approximate mathematical models and solution techniques, the yielding of a functionally graded material cylindrical pressure vessel is studied. Different solution techniques such as closed form solution, FE solution of ABAQUS and semi-analytical solution of variable material properties are used. Based on the von Mises and Tresca’s yield criteria, the shape of plastic zone are obtained and compared. The influences of different structural parameters as well as the effect of failure criterion upon the results are studied. Accordingly, some justifications are made regarding the selection of different material parameters or failure models.