Effect of moisture on the nonlinear viscoelastic fracture behavior of polymer nanocompsites: a finite deformation phase-field model

Abstract

The mechanisms underlying damage in high-performance polymer nanocomposites are remarkably affected by hygrothermal conditions. In this study, we develop a phase-field formulation to investigate the influence of hygrothermal conditions on the nonlinear viscoelastic fracture behavior of epoxy resins and their nanocomposites at finite deformation. For this, the Helmholtz free energy, capturing the effect of temperature and moisture and nanoparticle contents, is defined based on an additive decomposition of the energy into an equilibrium, a non-equilibrium, and a volumetric contribution with different definitions under tensile and compressive loading. The coupled displacement phase-field problem is solved using a quasi-Newton monolithic algorithm and a staggered solution scheme. Numerical examples show that the monolithic algorithm is more efficient. Simulations are performed to investigate the effect of temperature, deformation rate, and moisture content on the force–displacement response of boehmite nanoparticle/epoxy samples in benchmark numerical problems. Comparing numerical predictions and experimental data for compact-tension tests shows good agreement at different nanoparticle contents. Also, the model’s capability to predict fracture patterns is evaluated using simulations of single-edge notched nanocomposite plates under tensile and shear loading.

Causal factors concerning the texture of French fries manufactured at industrial scale

“…Models applied to amorphous glassy polymers seem most relevant ( Dal et al, 2022 ). This phase field can be coupled to general large deformation finite element models ( Arash et al, 2022 ).…”

Hygroscopic phase field fracture modelling of composite materials

“…Only very recently two studies have been published in this regard. Arash et al [47] presented a phenomenological phase field-based model to investigate the effect of hydrothermal effects on the failure of the behaviour of nanocomposite materials. In this study, the transport problem was not explicitly resolved and, instead, a uniform moisture distribution was assumed.…”

Phase Field Modeling of Crack Growth with Viscoplasticity

“…Xie et al [29] developed a new phase field model for creep cracks in elasto-plastic materials by introducing a degradation function of creep strain acting on fracture toughness. Arash et al [30,31] studied the fracture behavior of nanocomposites using the thermos-viscoelastic and nonlinear viscoelastic models. Ullah et al [32] and ZeiEldin et al [33] analyzed the Casson hybrid nanofluid by using a Cattaneo-Christov double-diffusion model.…”