Researchers Boyang Gu, Adrian Diaz, Yang Li, and Youping Chen from the University of Texas at Austin have developed a new computational method to simulate the complex interactions between dislocations and cracks in crystalline materials. Their work, published in the Journal of the Mechanics and Physics of Solids, focuses on improving the understanding of material failure processes, which is crucial for the energy industry, particularly in designing and maintaining infrastructure that can withstand extreme conditions.
The team has created a finite element method that can simulate the dynamic processes involving both dislocation motion and crack propagation. This method numerically solves the Concurrent Atomistic-Continuum (CAC) formulation of the conservation of linear momentum. By discretizing a crystalline material at the unit-cell level using 6-node prism elements, the method allows dislocations and cracks to nucleate and propagate along element facets. This approach enables researchers to model the behavior of materials under stress at the nanoscale and mesoscale levels.
In their study, the researchers demonstrated the method’s accuracy by simulating the initiation and propagation of dislocations and cracks in single-crystal copper, iron, and silicon. The results were in excellent agreement with fully atomistic molecular dynamics simulations. Additionally, mesoscale simulations of single-crystal copper showed the method’s ability to capture size-dependent brittle and ductile behavior. Under plane-strain conditions, the copper model fractured in a brittle manner, while a fully three-dimensional model exhibited curved and intersecting dislocations that blunted the crack tip and prevented crack propagation, resulting in ductile behavior.
The practical applications of this research for the energy sector are significant. Understanding and predicting material failure is essential for designing safer and more efficient energy infrastructure, such as pipelines, reactors, and storage facilities. By providing a more accurate and efficient way to simulate material behavior, this method can help engineers develop materials that are more resistant to failure, ultimately leading to improved safety and reduced costs in the energy industry.
The researchers highlight the accuracy, efficiency, and applicability of their method, suggesting that it could be a valuable tool for material scientists and engineers working in the energy sector. As the demand for energy continues to grow, the need for advanced materials that can withstand extreme conditions becomes increasingly important. This new computational method offers a promising approach to meeting that need.
This article is based on research available at arXiv.