Strain Measures for Rigid Crushable Foam in Uniaxial Compression

Abstract

Progressive collapse deformation mechanisms in Rohacell‐51WF foam during uniaxial compression has been studied. Measures of a macroscopic engineering strain are identified. The elastic and plastic parts of a macroscopic engineering strain can be predicted by using the compression failure strain, lock‐up strain, and time dependent elastic and plastic parts of lock‐up strain, which are material parameters. Identification of strain measures in a uniaxial compression test is essential to get material parameters for an elastoplastic model. The viscoelastic recovery property of Rohacell‐51WF foam is also described.

Mechanical properties of multifunctional foam core materials

“…[47][48][49]. They are generally known to have excellent mechanical properties, high thermal/ dimensional stability, very low resin uptake, high impact strength, as well as excellent resistance against most solvents.…”

On the Characterisation of Foam and Micro‐lattice Materials used in Sandwich Construction1

“…At a value of compression strain, there are regions of crushed foam (A′B′F′E′) and non‐crushed foam (E′F′D′C′). Li and Mines [16] quantify the strain through the block, and relate global strains to local strains. The analysis assumes negligible Poisson's effect for both initiation and progression of crush, i.e.…”

“…a one‐dimensional analysis is assumed. The length dimensions in Figure 7 can be quantified as [16]: where L is the original length, ɛ the total engineering strain, ɛ y the failure engineering strain, ɛ L the lock up/densification engineering strain and ɛ the initial engineering crush strain. In other words, L linearly increases with engineering compression strain ( ɛ ) and L linearly decreases with engineering compression strain ( ɛ ).…”

Failure mechanism of PMI foam core sandwich beam in bending

“…Considerable studies have been carried out on the failure analysis of PMI foams. Li and Mines have studied the compressive process of PMI foam under uniaxial compression [2] and the crush behavior under a series of tests [3]. Chen et al have investigated the influence of foam structure on the macroscopic properties of PMI foam [4].…”