Investigation of accelerated moving load on dynamic response of FG Timoshenko nanobeam in thermal environment based on nonlocal strain gradient theory

Forces in Mechanics, Journal Year: 2024, Volume and Issue: 16, P. 100280 - 100280

Published: June 18, 2024

For the first time, this paper investigates forced vibrations of a functionally graded (FG) nanobeam with an accelerating moving load in thermal environment. There is no exact coupling solution for accelerated load, so aims to provide method obtain accurate nanoscale structures load. The equations motion are derived using Timoshenko's beam theory and nonlocal strain gradient (NSGT). Laplace has been used solve differential equations. Then, by inverting from coupled equations, temporal response FG constant acceleration initial velocity environment was obtained. natural frequency compared previous works validity had acceptable results. Finally, effect parameters such as changes force, negative acceleration, power law index material, different temperatures, parameter, longitudinal scale parameter on maximum dynamic displacement investigated. These results can be better design nanostructures loads. Considering sensitivity data analysis nano dimensions, it necessary analytical these dimensions reduce error percentage zero. which presented work time.

Language: Английский

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Elastoplastic Indentation Response of Sigmoid/Power Functionally Graded Ceramics Structures

Polymers, Journal Year: 2022, Volume and Issue: 14(6), P. 1225 - 1225

Published: March 17, 2022

Due to the applicability of new advanced functionally graded materials (FGMs) in numerous tribological systems, this manuscript aims present computational and empirical indentation models investigate elastoplastic response FG substrate under an indention process with spherical rigid punch. The spatial variation ceramic volume fraction through specimen thickness is portrayed using power law sigmoid functions. effective properties two-constituent FGM are evaluated by employing a modified Tamura–Tomota–Ozawa (TTO) model. Bilinear hardening behavior considered analysis. finite element procedure developed predict contact pressure, horizontal displacement, vertical deformation, permanent deformation structure cylindrical indentation. forms for were assigned. Model validation experimental works was considered. convergence mesh solution checked. Numerical studies performed illustrate influence gradation function, index, parameters on von Mises stresses, horizontal/vertical displacements, plastic deformation. model can help engineers designers selection optimum function index based their applications.

Language: Английский

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Analytical solution for size-dependent nonlinear behavior of AFM microcantilever with assembled probe in liquid environments

Mechanics of Advanced Materials and Structures, Journal Year: 2023, Volume and Issue: unknown, P. 1 - 18

Published: Oct. 6, 2023

AbstractUsing modified strain gradient theory, this study aims to examine the size-dependent nonlinear behavior of atomic force microscopy (AFM) with an assembled cantilever probe (ACP) in various liquid environments. The largest contribution theory lies its consideration material length scale parameter (MLSP) analyze effect size on physical characteristics. When studying ACP liquids, hydrodynamic creates a different compared beam enclosed air. In study, Hamilton’s principle is used derive partial differential equation (PDE) motion and associated boundary conditions (BCs) To achieve this, combination Euler-Bernoulli’s concepts are employed. As next step, reduced order model system developed using Galerkin method. assess frequency response environments, perturbation technique, including method multiple scales (MMS), applied model. also calculates resonance frequencies, phase planes, stability, potential function analytically. results indicate that becomes as ratio thickness MLSP decreases. Several factors, well viscous damping coefficient, can influence jump phenomenon. Furthermore, amplitude environments demonstrate increase (h/l) decrease leftward shift diagram. This phenomenon indicative softening exhibited by system. Lastly, paper examines validity accuracy MMS solution comparing it numerical solution.Keywords: Atomic microscopymodified theoryperturbation techniquesnonlinear behaviormultiple Disclosure statementNo conflict interest was reported author(s).

Language: Английский

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Vibration and Reliability Analysis of Non-Uniform Composite Beam under Random Load

Applied Sciences, Journal Year: 2022, Volume and Issue: 12(5), P. 2700 - 2700

Published: March 4, 2022

Non-uniform structures and composite materials have advantages in engineering applications, such as light weight design, multi-functionality, better buckling/flutter load capacity. For under dynamic loading conditions, reliability is a key problem to be analyzed during practical operations. However, there little research work on non-uniform structural analysis random load. The forced vibration response of beam firstly solved by the Adomian Decomposition Method (ADM) iterative process for analysis. Different variation laws cross-section rigidity mass distribution along length are analyzed. Various angular frequency amplitude base motion acceleration following Gaussian considered. Influences different excitations design responses studied. larger mean variance excitation leads smaller strain beam, while greater will induce higher maximum values lower reliability. influences increases with increment taper ratios host layer. iteration mathematical model numerical solutions proposed this paper can used solve analyze general arbitrary certain period time.

Language: Английский

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Indentation Response of Power and Sigmoid Functionally Graded PSZ/NiCrAlY Composites

International Journal of Applied Mechanics, Journal Year: 2022, Volume and Issue: 14(04)

Published: April 28, 2022

Owing to their superior mechanical properties, functionally graded materials (FGMs) are currently applicable for many tribological systems, which increased the need a rapid prediction tool of hardness and wear behavior these materials. To this end, paper aims present empirical equations predict residual indentation deformation PSZ/NiCrAlY composite FGM that could give indication on material rates at different loads. The were derived two common gradient laws, power (P-FGM) sigmoid (S-FGM), based numerical results obtained validated with experimental in study. by simulating experiments using commercial finite element software considering all elastic plastic properties. influence index, law displacement force-indentation response, contact pressure distribution, stains, surface profile evolutions, deformations studied. showed force larger P-FGM than S-FGM indices. is indices due higher PSZ ceramic phase area S-FGM. was normalized respect its value pure matrix highlighted independence ratio load. Finally, index both functions.

Language: Английский

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