Unified tensile fracture criterion

Area of Science:

• Materials Science
• Solid Mechanics
• Fracture Mechanics

Background:

• Classical failure criteria (maximum normal stress, Tresca, Mohr-Coulomb, von Mises) are insufficient for explaining the tensile fracture behavior of bulk metallic glasses (BMGs).
• Existing models do not adequately capture the complex stress states leading to fracture in these advanced materials.

Purpose of the Study:

• To propose a novel ellipse criterion for predicting material failure.
• To demonstrate the unified applicability of the ellipse criterion to BMGs and other materials.
• To provide a more accurate failure prediction model for engineering applications.

Main Methods:

• Development of a new ellipse-based failure criterion.
• Application and validation of the ellipse criterion against experimental data for BMGs.
• Comparative analysis with classical failure criteria.

Main Results:

• The proposed ellipse criterion successfully describes the tensile fracture behavior of BMGs, outperforming classical criteria.
• The criterion unifies the four classical failure criteria based on the ratio alpha = tau(0)/sigma(0).
• The ellipse criterion shows broad applicability to various material types beyond BMGs.

Conclusions:

• The ellipse criterion offers a superior and unified approach to predicting material failure, particularly for bulk metallic glasses.
• This new criterion enhances the understanding of fracture mechanics in advanced materials.
• The findings pave the way for improved material design and performance prediction.