Three‐dimensional fatigue crack growth simulation and fatigue life assessment based on finite element analysis

Abstract

Damage tolerance design allows manufactures to assess fatigue crack propagation of components containing initial defects. A new modeling approach is proposed to carry out a systematic crack growth analysis based on an analytical method using reduced order models and three‐dimensional (3D) finite element (FE)‐based fatigue crack growth (FCG) analysis. 3D FE‐based FCG analysis is adopted as an advanced modeling approach for component geometries without any simplifications with respect to crack front shape or planarity of the crack path. The FE‐based FCG approach was verified and validated in two different stages: Ti‐6Al‐4V plate geometry with three different single elliptical crack configurations and Al 2024‐T3 specimens with two different multiple crack configurations. The analytical FCG approach was developed to estimate crack front evolution and crack growth life for three different elliptical cracks to verify the FE‐based approach. Experimental data of Al 2024‐T3 specimens with multi‐edge cracks was used to further validate the FE‐based FCG approach. The FE‐based FCG approach proved to be both accurate and powerful in assessing crack propagation life and crack paths of structural parts.

Effect of specimen thickness on fatigue crack shape evolution for aluminum alloy

“…In recent years, the evolution of fatigue crack shapes has emerged as a topic of considerable interest. Numerous research studies have been undertaken to investigate crack shapes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], and the collective findings suggest that finite thickness specimens exhibit a phenomenon known as the "tunneling effect." Specifically, in specimens with an initially straight crack that eventually penetrates, the central crack front advances ahead of all others as the loading cycles progress.…”

An adaptive extended finite element based crack propagation analysis method

“…In engineering structures, the existence of cracks will reduce strength and life, causing serious safety accidents and economic losses. In recent years, with the rapid development of computational science, computational mechanics is widely used in crack analysis, including finite element method (FEM) [1][2][3], meshless methods (MMs) [4][5][6], boundary element method (BEM) [7][8][9][10], XFEM [11][12][13], etc. However, the traditional finite element method relies too much on the mesh, which leads to the complexity of the pre-processing of crack growth.…”

A combination of extended finite element method and the Kriging model based crack identification method

“…The crack inversion based on numerical technique includes forward analysis and objective function minimization. Numerical methods which can be used for forward analysis include finite element method [1][2][3], meshless method [4][5][6], boundary element method [7][8][9][10], and XFEM [11][12][13], etc. The traditional finite element method relies too much on mesh, and the mesh needs to be re-divided in each iteration.…”