Evaluation of Fracture Properties of Two Metallic Materials under Hydrogen Gas Conditions by Using XFEM

Abstract

Interest in hydrogen energy is increasing due to its eco-friendliness and ease of use. Research is being conducted to produce and use hydrogen in various fields such as hydrogen vehicles and nuclear power plants. However, considering the purity requirements and the need for containment, experiments with hydrogen have several constraints, such as accounting for the charging and purging time. In this study, the effects of hydrogen gas on the fracture properties of T6 heat-treated 6061 aluminum alloy (Al6061-T6) and Chromium-molybdenum steel (SA372) were investigated using the extended finite element method (XFEM). First, numerical analyses for smooth and notched slow strain rate tensile test specimens under air and hydrogen gas conditions were conducted using a multi-island genetic algorithm and XFEM to derive true stress–strain data and damage parameters of the two materials based on experimental results. Second, the fracture resistance curves of ½T-compact tension (CT) specimens made of SA372 steel were determined by crack growth analyses using the calibrated parameters. The estimated JQ values were compared with those from experiments to validate the method, of which differences were less than 20%. Finally, the fracture properties of Al6061-T6 alloy were predicted using the same method with ½T-CT specimens.

XFEM for Composites, Biological, and Bioinspired Materials: A Review

“…For an aluminum alloy sample, Gairola and Jayaganthan [51] correctly predicted the material fracture toughness, suggesting that 3D XFEM simulations are slightly better than 2D. Kim et al [58] showed the effects of hydrogen gas on the fracture behavior of an aluminum alloy by simulating fracture resistance curves of compact tension specimens. The XFEM load and displacement curves were within 5% of the experimental conditions.…”

Predicting Stress Intensity Factor for Aluminum 6062 T6 Material in L-Shaped Lower Control Arm (LCA) Design Using Extended Finite Element Analysis

“…To model the initial crack and crack propagation in Abaqus/CAE using the XFEM method, it is necessary to adopt the linear traction–separation law. This law is characterized by three parameters: cohesion force, cohesion energy, and critical displacement [ 15 ]. The evolution of the fracture is modeled according to three specific stress-based criteria: maximum principal stress (MAXPS), maximum nominal stress (MAXS), quadratic nominal stress (QUADS).…”

“…It is also modeled on three criteria specifically based on strain: maximum principal strain (MAXPE), maximum nominal strain (MAXE), and quadratic nominal strain (QUADE). In the literature [ 15 , 20 ], we find that several studies are based on the MAXPS criterion to model the initiation and propagation of the crack. In our study, we based our analysis on the maximum nominal stress (MAXPS) and critical displacement.…”

“…In the literature, Kishorekanna et al [ 15 ] conducted a performance analysis of a U-shaped pre-cracked lower control arm by applying the finite element method. This study integrated the concepts of fracture mechanics to evaluate the stress intensity factor (KI) in the stress concentration zone of the lower control arm.…”