Elastic–plastic analysis of functionally graded rotating disks with variable thickness and temperature-dependent material properties under mechanical loading and unloading

We present a numerical approach for material optimization of metal-ceramic functionally graded materials (FGMs) with temperature-dependent material properties. We solve the non-linear heterogeneous thermoelasticity equations in 2D under plane strain conditions and consider examples in which the material composition varies along the radial direction of a hollow cylinder under thermomechanical loading. A space of shape-preserving splines is used to search for the optimal volume fraction function which minimizes stresses or minimizes mass under stress constraints. The control points (design variables) that define the volume fraction spline function are independent of the grid used in the numerical solution of the thermoelastic problem. We introduce new temperature-dependent objective functions and constraints. The rule of mixture and the modified Mori-Tanaka with the fuzzy inference scheme are used to compute effective properties for the material mixtures. The different micromechanics models lead to optimal solutions that are similar qualitatively. To compute the temperature-dependent critical stresses for the mixture, we use, for lack of experimental data, the rule-of-mixture. When a scalar stress measure is minimized, we obtain optimal volume fraction functions that feature multiple graded regions alternating with non-graded layers, or even non-monotonic profiles. The dominant factor for the existence of such local minimizers is the non-linear dependence of the critical stresses of the ceramic component on temperature. These results show that, in certain cases, using power-law type functions to represent the material gradation in FGMs is too restrictive.

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Thermoelastic creep analysis of a functionally graded various thickness rotating disk with temperature-dependent material properties

International Journal of Pressure Vessels and Piping ◽

10.1016/j.ijpvp.2013.05.001 ◽

2013 ◽

Vol 111-112 ◽

pp. 63-74 ◽

Cited By ~ 18

Author(s):

S.A. Hosseini Kordkheili ◽

M. Livani

Keyword(s):

Material Properties ◽

Rotating Disk ◽

Functionally Graded ◽

Temperature Dependent ◽

Creep Analysis

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Geometrically nonlinear dynamic response and vibration of shear deformable eccentrically stiffened functionally graded material cylindrical panels subjected to thermal, mechanical, and blast loads

Journal of Sandwich Structures & Materials ◽

10.1177/1099636218765603 ◽

2018 ◽

Vol 22 (3) ◽

pp. 658-688 ◽

Cited By ~ 2

Author(s):

Nguyen Dinh Duc ◽

Ngo Duc Tuan ◽

Pham Hong Cong ◽

Ngo Dinh Dat ◽

Nguyen Dinh Khoa

Keyword(s):

Dynamic Response ◽

Functionally Graded Material ◽

Material Properties ◽

Nonlinear Dynamic ◽

Functionally Graded ◽

Blast Loads ◽

Temperature Dependent ◽

Nonlinear Dynamic Response ◽

Cylindrical Panels ◽

Graded Material

Based on the first order shear deformation shell theory, this paper presents an analysis of the nonlinear dynamic response and vibration of imperfect eccentrically stiffened functionally graded material (ES-FGM) cylindrical panels subjected to mechanical, thermal, and blast loads resting on elastic foundations. The material properties are assumed to be temperature-dependent and graded in the thickness direction according to simple power-law distribution in terms of the volume fractions of the constituents. Both functionally graded material cylindrical panels and stiffeners having temperature-dependent properties are deformed under temperature, simultaneously. Numerical results for the dynamic response of the imperfect ES-FGM cylindrical panels with two cases of boundary conditions are obtained by the Galerkin method and fourth-order Runge–Kutta method. The results show the effects of geometrical parameters, material properties, imperfections, mechanical and blast loads, temperature, elastic foundations and boundary conditions on the nonlinear dynamic response of the imperfect ES-FGM cylindrical panels. The obtained numerical results are validated by comparing with other results reported in the open literature.

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