Elastic moduli inheritance and the weakest link in bulk metallic glasses

Area of Science:

• Materials Science
• Solid Mechanics
• Amorphous Materials

Background:

• Bulk metallic glasses (BMGs) are amorphous alloys lacking long-range atomic order.
• Understanding the mechanical properties of BMGs is crucial for their application.
• The relationship between composition and elastic properties in BMGs requires further elucidation.

Purpose of the Study:

• To investigate the origin of Young's modulus and shear modulus in bulk metallic glasses.
• To explore the role of solvent components in determining the elastic behavior of BMGs.
• To understand the deformation mechanisms in elastically deformed BMGs.

Main Methods:

• Theoretical analysis of elastic moduli inheritance from solvent components.
• In situ neutron diffraction studies on elastically deformed BMGs.
• Analysis of atomic-level deformation mechanisms in amorphous structures.

Main Results:

• BMGs inherit their Young's and shear moduli from the solvent elements.
• Preferential straining of solvent-rich configurations within atomic clusters was observed.
• Inhomogeneous deformation and a hierarchy of atomic bonds contribute to BMG behavior.

Conclusions:

• The elastic properties of BMGs are strongly influenced by their solvent components.
• BMGs exhibit inhomogeneous deformation, consistent with a rubberlike viscoelastic model.
• The findings provide insights into the structure-property relationships in amorphous metallic materials.