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کلیدواژهها
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Thermo-mechanical stability, Flexomagnetic, Strain gradient theory, Rectangular nano-plate, Geometrical imperfection
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چکیده
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This study presents a comprehensive thermo-mechanical stability analysis of an imperfect rectangular piezoflexomagnetic
nano-plate. The theoretical model simultaneously incorporates both piezomagnetic and direct
flexomagnetic effects, enabling a more comprehensive representation of magneto-mechanical coupling phenomena
at the nanoscale. To capture the size-dependent behavior inherent to such nano-structures, the
strain-gradient theory is employed through the inclusion of a material length-scale parameter. The governing
differential equations and corresponding boundary conditions are derived based on the von Kármán nonlinear
strain–displacement relations, classical plate theory, and principle of minimum total potential energy. Closedform
analytical solutions are obtained for critical buckling and post-buckling behavior under mechanical,
thermal, and coupled thermo-mechanical loading conditions for both roller and hinge edge supports. The
analytical formulation is validated through comparisons with benchmark results reported in the literature.
A parametric investigation is conducted to evaluate the effects of key parameters—including flexomagnetic
coupling, aspect ratio, boundary conditions, initial geometric imperfection, and thermal loading—on the
buckling and post-buckling response of the nano-plate. The numerical results reveal that the influence of
the flexomagnetic effect is more pronounced under uniaxial in-plane loading compared to biaxial loading.
Additionally, in biaxial loading conditions, the impact of the flexomagnetic property is significantly greater for
aspect ratios less than unity. The stability performance of the nano-plate shows consistent improvement due to
flexomagnetic effects for both uniaxial and biaxial loading scenarios. Size effects play a critical role in nanoscale
structural behavior, as evidenced by the substantial increase in critical buckling load with the length-scale
parameter. Geometric imperfections generally lower the critical load, though their impact on the post-buckling
response varies with both imperfection magnitude and boundary constraints. Thermal loading demonstrates
a more pronounced destabilizing effect compared to purely mechanical loading, particularly in plates with
imperfections. Boundary conditions substantially influence the structural response: roller supports offer greater
initial load capacity, whereas hinged supports develop enhanced membrane stiffening at larger deformation
amplitudes. These findings offer valuable insights for the design and development of smart two-dimensional
nano-devices where flexomagnetic coupling can be utilized for enhanced stability control.
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