The yielding transition in amorphous solids under oscillatory shear deformation

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Materials Science

Background:

• Amorphous solids are common in nature and technology, with mechanical properties crucial for their application.
• Understanding the yielding behavior of amorphous solids under stress is essential but remains challenging due to gradual transitions and preparation-dependent responses.
• Existing theoretical models struggle to explain the observed yielding phenomena in these materials.

Purpose of the Study:

• To investigate the yielding transition in amorphous solids using a reliable probing method.
• To determine if a sharp yielding transition exists and its independence from material preparation history.
• To analyze the role of avalanches in the yielding process and their relation to the transition.

Main Methods:

• Extensive computer simulations were performed on model glass systems of various sizes.
• Oscillatory deformation was employed as a precise method to probe the yielding transition.
• Statistical analysis of avalanche events was conducted to characterize the yielding behavior.

Main Results:

• Cyclically deformed model glasses exhibit a sharply defined yielding transition.
• The yielding transition characteristics were found to be independent of the preparation history of the amorphous solids.
• Avalanche statistics showed no precursor signature of the transition but dramatic qualitative changes across the yielding point.

Conclusions:

• Oscillatory deformation provides a reliable method for identifying a sharp yielding transition in amorphous solids.
• The yielding of amorphous solids is a more defined transition than previously thought, not significantly influenced by preparation.
• Avalanche dynamics undergo significant qualitative changes at the yielding transition, offering new insights into material failure mechanisms.