Amorphous intergranular films as toughening structural features

By Zhiliang Pan, T. Rupert. 2015

137 citations recorded by the source corpus.

The ability of amorphous intergranular films to mitigate damage formation at grain boundaries is studied with molecular dynamics simulations. We find that such films can alter both crack nucleation and crack growth rates by efficiently absorbing dislocations, with thicker films being more effective sinks. Local plastic strain brought by incoming dislocations is diffused into a triangular region within the amorphous film and is accommodated by a flow of boundary atoms which resembles a vortex shape; this vortex grows inside of the amorphous intergranular film as more dislocations are absorbed until it reaches the opposite amorphous-crystalline interface, after which cracks can finally be nucleated. Even after nucleation, these cracks grow more sluggishly in an amorphous intergranular film than they do along a clean grain boundary, since the driving force for crack growth is lower in the amorphous film. The results presented here suggest that amorphous intergranular films can act as toughening features within a microstructure, and thus are promising for designing nanostructured materials with better ductility and fracture toughness.

Subfields: Ceramics and Composites, Materials Chemistry, Mechanical Engineering

View Paper: https://www.semanticscholar.org/paper/935f8aabef1cc84f435f2288fa10bc923dee715e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Ceramics and Composites

1. Q. Wang

In Materials Chemistry

1. G. Rohrer
2. P. Cantwell
3. M. Harmer
4. A. Krause
5. Jeffrey M. Rickman
6. T. Rupert
7. Q. Wang
8. T. Frolov

In Mechanical Engineering

1. A. Krause
2. Jeffrey M. Rickman
3. T. Rupert
4. Q. Wang
5. G. Rohrer
6. M. Harmer
7. P. Cantwell
8. T. Frolov

Citations in the corpus

• Amorphous–nanocrystalline alloys: fabrication, properties, and applications (2019, background): “In 2015, Khalajhedayati and Rupert [55] observed GB complexion in a nanocrystalline CueZr alloy.”
• Grain Boundary Complexion Transitions (2020, background): “Rupert and coworkers demonstrated that amorphous intergranular films both toughen (66, 67) and strengthen (43, 68) nanocrystalline metals.”