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Numerical Fatigue Crack Growth on Compact Tension Specimens under Mode I and Mixed-Mode (I+II) Loading.
Rui F Martins1,2, José Xavier1,2, João Caldeira1
1UNIDEMI, Department of Mechanical and Industrial Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
Materials (Basel, Switzerland)
|September 28, 2024
Summary
This study validates numerical stress intensity factor calculations for Compact Tension (CT) specimens under various loading modes. The Extended Finite Element Method (XFEM) effectively simulates fatigue crack growth in AISI 316L steel.
Area of Science:
- Mechanical Engineering
- Materials Science
- Computational Mechanics
Background:
- Compact Tension (CT) specimens are crucial for fracture mechanics testing.
- Accurate stress intensity factor (K) calculations are vital for predicting material failure.
- Understanding mixed-mode loading effects (Modes I and II) is essential for real-world applications.
Purpose of the Study:
- To numerically analyze stress intensity factors (K) in CT specimens under pure mode I and mixed-mode (I+II) loading.
- To validate numerical results against analytical solutions for pure mode I loading.
- To investigate fatigue crack growth using the Extended Finite Element Method (XFEM) under mode I loading.
Main Methods:
- Numerical analysis using Abaqus® 2022 for stress intensity factor (K) calculations.
- Comparison of numerical K values with analytical solutions for pure mode I loading.
- Fatigue crack growth simulation employing the Extended Finite Element Method (XFEM) and Paris Law for AISI 316L stainless steel.
Main Results:
- Excellent agreement was observed between numerical and analytical stress intensity factors (KI) under pure mode I loading.
- Numerical stress intensity factors (KI, KII, KIII) were successfully obtained for mixed-mode loading.
- The Extended Finite Element Method (XFEM) demonstrated effectiveness in predicting crack propagation direction and growth.
Conclusions:
- Numerical methods, particularly Abaqus®, provide accurate stress intensity factor calculations for CT specimens.
- XFEM is a reliable tool for simulating fatigue crack growth, contingent upon appropriate mesh refinement.
- The study confirms the applicability of these methods for analyzing crack behavior in materials like AISI 316L stainless steel.
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