The objective of this paper is to study the deformation in a homogeneous isotropic thermoelastic solid using modified couple stress theory subjected to inclined load with two temperatures with multi-dual-phase-lag heat transfer. Uniformly distributed and linearly distributed forces have been applied to find the functionality of the problem. Laplace and Fourier transform technique is applied to obtain the solutions of the governing equations. The displacement components, conductive temperature, stress components and couple stress are obtained in the transformed domain. A numerical inversion technique has been used to obtain the solutions in the physical domain. The effect of two temperature and inclined load is depicted graphically on the resulted quantities.

In this research work 3 wt. % and 5 wt. % of tungsten oxide (WO₃) particulates are reinforced the Al-5Mg-5Zn alloy. Two-step liquid stir casting processing route is used for the development of these particulate reinforced aluminium alloy metal matrix composites. The mechanical and the tribological properties such as Brinell hardness, impact toughness and dry sliding wear resistance of the as-cast Al-5Mg-5Zn alloy matrix and the prepared Al-5Mg-5Zn/WO₃ particulate metal matrix composites are analysed according to ASTM standards. The worn-out surfaces of the test samples during the wear test of the developed compositions are also analysed by using optical microscopy to express the patterns of wear. The results show that the addition of WO₃ particulates improved the hardness as well as dry sliding wear resistance of the Al-5Mg-5Zn alloy and these properties are also increased with the increase in the wt. % of WO₃. The value of impact toughness decreases with the addition of WO₃ particulates as well as increasing the wt. % of WO₃ particulates.

The present research considers the stability and corresponding modes of two axially compressed joined cross-ply laminated conical shells. The joined conical shells are the general case of a wide area of joined structures, including cylinder-cone, cone-plate, cylinder-plate, stepped thickness cone and stepped thickness cylinder. The principle of minimum potential energy is applied to extract the equilibrium equations under the thin Donnell type shell theory assumptions. The analytical procedure is used to solve the equations by applying trigonometric and series responses in circumferential and meridional directions, respectively. To ensure from accuracy and correctness of the results, the finite element analysis is done for various stacking sequences and the analytical results are compared and validated with other literature and finite element results. Finally, the effects of some parameters including semi-vertex angles, meridional lengths, number of layers and various kinds of simply supported and clamped boundary conditions at both ends are studied.

This research is devoted to investigate the thermal buckling analysis behaviour of laminated composite plates, by applying an analytical model based on a refined plate theory (RPT) with five independent unknown variables. The theory accounts for parabolic distribution of the transvers shear strains through the plate thickness, and satisfied the zero traction boundary condition on the surface without using shear correction factors, hence a shear correction factor is not required. The governing differential equations and associated boundary conditions are derived by employing the principle of virtual work and solved via Navier-type analytical procedure to obtain critical buckling temperature for simply supported boundary condition of symmetric and antisymmetric cross-ply and angle-ply laminated plates. MATLAB 2018 program is used to investigate the effect of thickness ratio (a/h), aspect ratio (a/b), orthogonality ratio (E₁/E₂), coefficient of thermal expansion ratio (α₂/α₁) and numbers of layers on thermal buckling of laminated plate. It can be concluded that this theory gives good results when compared with other theory.

In order to develop a lightweight cement based composite with dual-function of EM wave absorption and thermal insulation, sandwich structure was designed to achieve excellent EM absorption capacity, and expanded perlite and carbon black were used as lightweight aggregates and EM absorbent, respectively. The EM absorption properties were studied by arching reflected method, and the results indicate that the sandwich structure design can obviously enhance the EM absorption capacity of cement composites. The sandwich structured composites exhibit better EM absorption properties than the traditional gradient multi-layer structured composites. The reflection loss of three-layer and four-layer sandwich structured composites can be less than -10 dB and -15 dB in the whole X-band. The thermal conductivity test results shows that the developed cement composites possess thermal insulation function.