Mechanical behavior and constitutive modeling of metal cores

Abstract

Studying the mechanical behavior of metal cores provides insight into the overall performance of structures comprising metal sandwich plates, and can help immensely in designing metal sandwich plates for specific engineering applications. In this study, the response of folded (corrugated) plate and pyramidal truss cores are explored under both quasistatic and dynamic loadings. In particular, two important characteristics of metal cores, the nonuniform hardening/softening evolution due to stressing in different directions and the rate-dependence, are discussed for different core topologies, including the square honeycomb core. In addition, the role of core behavior on the overall performance of sandwich plates is studied by employing a constitutive model for the elastic-plastic behavior of plastically compressible orthotropic materials [Xue et al. 2005]. The constitutive model is capable of capturing both the anisotropy of the core, associated with stressing in different directions, and its rate-dependence. The approach, based on employing the core constitutive model, not only significantly reduces the computation time, but also permits exploration of the role of each fundamental rate-dependent response of the metal core on the overall response of the metal sandwich plates.

Equivalent core concept for large-scale structural-level applications

“…The modulus of elasticity in the 2-direction, E 22 , can be obtained simply by scaling of the modulus of elasticity with the core relative density [10–14] …”

“…[12] tested the out-of-plane properties of metallic corrugated cores through experiments and the finite element method. In addition, sandwich plate bending responses have been investigated using homogenized models for corrugated, metallic honeycomb, and pyramidal truss cores [13, 14]. Zok et al.…”

Dynamic failure of honeycomb-core sandwich structures subjected to underwater impulsive loads

“…Deshpande [10,11], Xue [12,13] identified the constitutive relation for metallic sandwich accounting for the crush behavior of cores and plasticity in constituent. The dynamic response and failure mechanism involving face sheet stretching, core wall buckling and rupture have been studied with consideration of various core topological properties [5,6,[14][15][16][17][18].…”

Impact resistance and energy absorption of regular and functionally graded hexagonal honeycombs with cell wall material strain hardening

“…In contrast, under dynamic loads the response of cellular structures is mainly dominated by localized phenomena such as buckling and micro-inertial resistance [9,17,[28][29][30][31]. In addition, inelastic properties of the material can add significant complexity to the mechanical response of the structure.…”