Dynamic Stability and Static Stress State of a Sandwich Beam with a Metal Foam Core Using Three Modified Timoshenko Hypotheses

The objective of this work is to investigate the quasi-static plastic behavior of a fully clamped metal foam core sandwich beam transversely loaded by a flat punch. A rigid-plastic beam-on-foundation model is extended to study the local denting deformation of a metal foam core sandwich beam. The effects of local denting and core strength on the overall deformation are incorporated in the analysis. Analytical solutions are derived for three different regimes of post-yield deformation mechanisms. Additionally, finite element results are obtained. Comparisons of the present analytical predictions with numerical, previous experimental, and analytical results are presented, respectively. It is shown that local denting has a significant effect on the finite deflection response of the metal foam core sandwich structure. The load-carrying and energy absorption capacities of sandwich beams may be overestimated if the effect of local denting is neglected in analysis. It is demonstrated that the present analytial model can reasonably predict the behaviors of post-yield deformation of sandwich beams. Moreover, the present analytical method can be extended to predict the low velocity/energy impact problems of sandwich structures.

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Low-velocity heavy-mass impact response of slender metal foam core sandwich beam

Composite Structures ◽

10.1016/j.compstruct.2010.11.018 ◽

2011 ◽

Vol 93 (6) ◽

pp. 1526-1537 ◽

Cited By ~ 42

Author(s):

Qing Hua Qin ◽

T.J. Wang

Keyword(s):

Metal Foam ◽

Sandwich Beam ◽

Impact Response ◽

Foam Core ◽

Low Velocity

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A Comparison of the Structural Response of Clamped and Simply Supported Sandwich Beams With Aluminium Faces and a Metal Foam Core

Journal of Applied Mechanics ◽

10.1115/1.1875432 ◽

2004 ◽

Vol 72 (3) ◽

pp. 408-417 ◽

Cited By ~ 45

Author(s):

V. L. Tagarielli ◽

N. A. Fleck

Keyword(s):

Metal Foam ◽

Minimum Weight ◽

Sandwich Beam ◽

Limit Load ◽

Analytical Models ◽

Collapse Mechanism ◽

Foam Core ◽

Sandwich Beams ◽

Polymer Foam ◽

The Face

Plastic collapse modes for clamped sandwich beams have been investigated experimentally and theoretically for the case of aluminium face sheets and a metal foam core. Three initial collapse mechanisms have been identified and explored with the aid of a collapse mechanism map. It is shown that the effect of clamped boundary conditions is to drive the deformation mechanism towards plastic stretching of the face sheets. Consequently, the ultimate strength and level of energy absorption of the sandwich beam are set by the face sheet ductility. Limit load analyses have been performed and simple analytical models have been developed in order to predict the postyield response of the sandwich beams; these predictions are validated by both experiments and finite elements simulations. It is shown experimentally that the ductility of aluminium face sheets is enhanced when the faces are bonded to a metal foam core. Finally, minimum weight configurations for clamped aluminium sandwich beams are obtained using the analytical formulas for sandwich strength, and the optimal designs are compared with those for sandwich beams with composite faces and a polymer foam core.

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Analytical Solution for Pin-Supported Metal Foam Core Sandwich Beam with Local Denting

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.462-463.639 ◽

2011 ◽

Vol 462-463 ◽

pp. 639-644

Author(s):

Qing Hua Qin ◽

Jian Xun Zhang ◽

Tao Wang ◽

Tie Jun Wang

Keyword(s):

Carrying Capacity ◽

Metal Foam ◽

Sandwich Beam ◽

Structural Response ◽

Metallic Foam ◽

Foam Core ◽

Load Carrying Capacity ◽

Rigid Plastic ◽

Load Carrying ◽

Axial Stretching

Structural response of pin-supported metallic foam core sandwich beam is theoretically investigated. Effects of local denting and core strength and interaction of bending and axial stretching are considered in analysis. A rigid-plastic beam-on-foundation is employed to consider local denting deformation. The local denting continues during the overall deformation of sandwich beam. It is shown that upon neglecting the effect of local denting, the load-carrying capacity and energy absorption of sandwich beam may be overestimated, and the normal axial (membrane) force associated with plastic stretching substantially stiffens the sandwich beams.

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Large Deflection of a Pin-Supported Slender Geometrically Asymmetric Sandwich Beam under Transverse Loading

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.535-536.405 ◽

2013 ◽

Vol 535-536 ◽

pp. 405-408

Author(s):

Jian Xun Zhang ◽

Qing Hua Qin ◽

Wei Long Ai ◽

Zheng Jin Wang ◽

Tie Jun Wang

Keyword(s):

Sandwich Structure ◽

Large Deflection ◽

Metal Foam ◽

Yield Criterion ◽

Sandwich Beam ◽

Structural Response ◽

Foam Core ◽

Transverse Loading ◽

Flat Punch ◽

Axial Stretching

The objective of this work is to study the large deflection of a pin-supported slender geometrically asymmetric metal foam core sandwich beam under transverse loading by a flat punch. Based on the yield criterion for geometrically asymmetric metal foam core sandwich structure, analytical solution for the large deflection of a pin-supported slender sandwich beam is obtained, in which the interaction of bending and stretching induced by large deflection is considered. The finite element results confirm the accuracy of the analytical solutions. The effects of asymmetric factor and boundary condition on the structural response of the asymmetric sandwich beam are discussed in detail. It is shown that the axial stretching induced by large deflection plays an important role in the load-carrying and energy absorption capacities of geometrically asymmetric sandwich structure.

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