in many cases, a torsional shaft may be a thick-walled radially inhomogeneous cylindrical object. the hollow shafts made of functionally graded materials (fgms) are such kind of compositions which were studied in this paper. cylindrical fg shafts are composed of ceramic and metallic parts with power function distribution across the radial direction. the ceramic phase is isotropic elastic and th...

SOFCs running on jet fuel reformates are attractive to NASA for its uninhabited aerial vehicle and low emission alternative power missions. The US military has interest in fuel cells due to their lightweight, zero emission and low acoustic signatures in strategic zones. Jet fuels, such as Jet-A and JP-8 are already on board in many applications. If they can be reformed and used in fuel cells, m...

A heterogeneous object is referred to a solid component consisting of two or more material primitives distributed continuously or discontinuously within an object. Modeling and manufacturing of heterogeneous object (HO) have been paid much attention recently as the advent of rapid prototyping manufacturing technology, which makes it possible to fabricate the heterogeneous object. As the continu...

Based on fundamental equations of the elasticity theory, a unified higher-order shear deformation theory is developed for bending and free vibration analysis functionally graded (FG) microplates with porosities. The modified strain gradient employed to capture size effects. Bi-directional series hybrid shape functions are used solve problems. Several important effects including thickness-to-mat...

In this study, torsional wave propagation is investigated in a rod that are made of one and two dimensional functionally graded material. Firstly, the governing equations of the wave propagation in the functionally graded cylinder derived in polar coordinate. Secondly, finite difference method is used to discretize the equations. The Von Neumann stability approach is used to obtain the time ste...

in this paper, the effect of autofrettage process parameters on the ultimate pressure that functionally graded spherical vessel can tolerate are investigated. fgm properties and autofrettage pressure are considered as important parameters. assumptions are variation of properties of fgm in radial direction, the residual stress in the absence of bauschinger effect with the operation of variable m...

This paper deals with the determination of displacement function and thermal stresses of a finite length isotropic functionally graded hollow cylinder subjected to uniform temperature field. The solution of the governing thermoelastic equation is obtained, as suggested by Spencer et al. for anisotropic laminates.  Numerical calculations are also carried out for FGM (Functionally graded material...

In this paper, finite element elastic contact analysis of a functionally graded (FG) hollow brake disk in contact with pad, subjected to rotation, contact pressure and frictional heat is presented. The material properties vary through the thickness according to a power-law characterised by a grading index, n. The material property is purely steel at the core part and gradually moves and appr...

in this paper, the stability of a functionally graded magneto-electro-elastic (fg-mee) micro-beam under actuation of electrostatic pressure is studied. for this purpose euler-bernoulli beam theory and constitutive relations for magneto-electro-elastic (mee) materials have been used. we have supposed that material properties vary exponentially along the thickness direction of the micro-beam. gov...