Journal Articles
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/19884
Browse
5 results
Search Results
Item Computational model for the transverse stress analysis of FGM plates - An assessment(2013) Swaminathan, K.; Naveenkumar, D.T.This paper presents the complete theoretical formulation and the analytical solutions for stress analysis of functionally graded material (FGM) plates using First-order Shear Deformation Theory (FSDT). The material properties are assumed to be isotropic along the plane of the plate and vary through the thickness according to the power law function. The governing equations of equilibrium are derived using Principle of Minimum Potential Energy (PMPE) and the analytical solutions are obtained in closed-form using Navier's solution technique. The effect of variation of side-to-thickness ratio, modulus of elasticity ratio, edge ratio and the power law function on the behaviour of the plate is studied. Numerical results are presented for the transverse displacement, the in-plane and the transverse stresses. © 2013 CAFET-INNOVA TECHNICAL SOCIETY.Item Higher order refined computational models for the stability analysis of FGM plates - Analytical solutions(Elsevier Ltd, 2014) Swaminathan, K.; Naveenkumar, D.T.Analytical formulations and solutions for the stability analysis of simply supported Functionally Graded Material (FGM) sandwich plates hitherto not reported in the literature based on two higher-order refined computational models available in the literature are presented. These computational models are based on Taylor's series expansion of the displacements in the thickness coordinate and incorporate the realistic parabolic distribution of transverse strains through the plate thickness. One of them with twelve degrees-of-freedom considers the effects of both transverse shear and normal strain/stress while the other with nine degrees-of-freedom includes only the effect of transverse shear deformation. In addition another higher-order model and the first-order model developed by other investigators and available in the literature are also considered for the evaluation purpose. For mathematical modeling purposes, the Poisson's ratio of the material is considered as constant whereas Young's modulus is assumed to vary through the thickness according to the power law function. The governing equations of equilibrium for buckling analysis are obtained using the Principle of Minimum Potential Energy (PMPE). Solutions are obtained in closed form using Navier's technique by solving the eigenvalue problem. The comparison of the present results with the available elasticity solutions and the results computed independently using the first-order and another higher-order theory available in the literature shows that the higher-order refined theory with 12 degrees-of-freedom predicts the critical buckling load more accurately than all other theories considered in this paper. After establishing the accuracy of prediction, extensive numerical results for FGM sandwich plates using all the models are presented which will serve as a benchmark for future investigations. © 2014 Elsevier Masson SAS. All rights reserved.Item Thermo-elastic response of SUS316-Al2O3 functionally graded beams under various heat loads(Elsevier Ltd, 2017) Malik, P.; Kadoli, R.Geometric nonlinearity and temperature dependent material properties are accounted for in the theoretical analysis of time dependent thermo-elastic response of thin functionally graded material (FGM) SUS316-Al2O3 beam subjected to various heat loads. A two dimensional Lagrangian rectangular finite element is used to obtain the temperature distribution on the transverse plane of the beam. Nonlinear thermo-elastic deflection and thermal stresses are evaluated for various structural and thermal boundary conditions. Thermo-elastic oscillations are observed in case of beams subjected to step, concentrated line and shock heat load whereas thermo-elastic deflection is observed for beams subjected to moving heat load. As the thermal load increases, the nonlinear thermal deflection of FGM beam are higher compared to linear analysis. In general, temperature dependency of material properties influence the amplitude of thermal oscillations. High thermal stresses are induced in beams with pin-pin and clamp-pin boundary condition as compared to hinge-hinge beam. © 2017 Elsevier LtdItem Differential quadrature solution for vibration control of functionally graded beams with Terfenol-D layer(Elsevier Inc. usjcs@elsevier.com, 2020) Patil, M.A.; Kadoli, R.The governing differential equation of motion for vibration control of a functionally graded material (FGM) beam using magnetostrictive layers is solved using differential quadrature method(DQM). It is known that, when differential quadrature is implemented directly for the solution of governing differential equation for vibration control of beam, it is required to convert the generalised eigenvalue problem into standard eigenvalue problem. However in the present work, the original differential equation of vibration control of beam is be separated into two simpler second and fourth order differential equations using the separation of variables in conjunction with the characteristics equation of damped single degree of freedom system. Solution of corresponding two simpler differential equation also yields damped natural frequency and damped factor comparable to that of the former approach. It is to be noted that using either of the solutions using differential quadrature method ? point description of the physical domain at boundary is used to obtained the differential quadrature equations for the various boundary conditions of the beam. In order to assure the accuracy of formulation and solution using DQM, convergence behavior of natural frequencies is examined for five combinations of boundary conditions and comparison studies from the two solution approaches is presented. The effect of the location of the magnetostrictive layers, material properties and control parameters on the vibration suppression are investigated. © 2020 Elsevier Inc.Item Process-microstructural features for tailoring fatigue strength of wire arc additive manufactured functionally graded material of SS904L and Hastelloy C-276(Elsevier B.V., 2020) Kannan, A.; Subramaniyan, S.; Pravin Kumar, N.; Siva Shanmugam, N.; Vishnu, A.S.; Palguna, Y.Many engineered components on subjecting to critical environments require properties that slightly differs with location in the fabricated part. The inadequate understanding of wire arc additive manufacturing (WAAM) process-microstructural features correlation brings interests on the structural reliability of functionally graded materials (FGM), which limits the extensive use of this cutting edge technology. Gas metal arc welding (GMAW) based WAAM process was adopted to fabricate the FGM of super austenitic stainless steel SS904L and Hastelloy C-276 with excellent bonding. The micrographs revealed that the WAAM processed FGM was mainly composed of columnar and equiaxed dendrites and had noticeable inhomogeneous features along the built direction. Tensile test results of sample along the built direction revealed a yield strength of 311.08 MPa and tensile strength of 680.73 MPa. Cyclic loading results depicted that the WAAM processed FGM has a fatigue resistance of 156 Mpa after sustaining 2 × 106 cycles. As a result of the varying microstructural characteristics along the built direction, the failure was initiated and fractured at the SS904L weaker region. © 2020 Elsevier B.V.