A general phase-field model for fatigue failure in brittle and ductile solids

Abstract

In this work, the phase-field approach to fracture is extended to model fatigue failure in high- and low-cycle regime. The fracture energy degradation due to the repeated externally applied loads is introduced as a function of a local energy accumulation variable, which takes the structural loading history into account. To this end, a novel definition of the energy accumulation variable is proposed, allowing the fracture analysis at monotonic loading without the interference of the fatigue extension, thus making the framework generalised. Moreover, this definition includes the mean load influence of implicitly. The elastoplastic material model with the combined nonlinear isotropic and nonlinear kinematic hardening is introduced to account for cyclic plasticity. The ability of the proposed phenomenological approach to naturally recover main features of fatigue, including Paris law and Wöhler curve under different load ratios is presented through numerical examples and compared with experimental data from the author’s previous work. Physical interpretation of additional fatigue material parameter is explored through the parametric study.

A comparative review of peridynamics and phase-field models for engineering fracture mechanics

“…Table 2 lists the available phase-field fracture and damage models. The following models have been developed within the phase-field framework: brittle fracture [12,146,151,155,[186][187][188], fatigue [189][190][191][192][193][194][195][196], multi-field fracture [152,[197][198][199][200][201][202][203][204][205][206][207][208][209][210][211][212], frictional contact [213], plate/shell fracture [214][215][216][217][218][219][220] (where [220] solves some issues with the energy decomposition which were leading in [214,216] to unphysical results), three-dimensional fracture [151,202,[221]…”

Thermodynamically-consistent derivation and computation of twinning and fracture in brittle materials by means of phase-field approaches in the finite element method

“…Having the capability to model the microstructural evolution, it has been successfully adopted in the simulation of martensitic phase transformations [42,43], reconstructive phase transformations [44], phase transformations in liquids [45], dislocations [46], twinning [47], damage [48], and their interactions [49,50,51]. Initiated with the celebrated work by Francfort and Marigo on the variational approach to brittle fracture [52], where the total energy is minimized simultaneously with respect to the crack geometry and the displacement field, the concept of applying the phase-field method in fracture mechanics has gained significant interest in the literature [53,54,55,56,57,58,59,60,61,62,63,64,65]. Due to the thermodynamic driving forces, the evolution of interfaces (e.g., merging and branching of multiple cracks) is predicted with no additional effort [66].…”

Probabilistic failure mechanisms via Monte Carlo simulations of complex microstructures

“…The main driving force for these developments is the possibility to handle complex fracture phenomena within numerical methods in two and three dimensions. In recent years, several brittle [5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27] and ductile [28,29,30,31,32,33,34,35,36,37,38,39,40,41] phase-field fracture formulations have been proposed in the literature. These studies range from the modeling of Figure 1: Offshore Wind Turbine (source: germanoffshorewind.org) with different concrete microstructures.…”