Related Experiment Video
Updated: Oct 20, 2025

Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
Strength can be controlled by edge dislocations in refractory high-entropy alloys
Chanho Lee1,2, Francesco Maresca3,4, Rui Feng1,5
1Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN, 37996-2100, USA.
Abstract:
Energy efficiency is motivating the search for new high-temperature (high-T) metals. Some new body-centered-cubic (BCC) random multicomponent "high-entropy alloys (HEAs)" based on refractory elements (Cr-Mo-Nb-Ta-V-W-Hf-Ti-Zr) possess exceptional strengths at high temperatures but the physical origins of this outstanding behavior are not known. Here we show, using integrated in-situ neutron-diffraction (ND), high-resolution transmission electron microscopy (HRTEM), and recent theory, that the high strength and strength retention of a NbTaTiV alloy and a high-strength/low-density CrMoNbV alloy are attributable to edge dislocations. This finding is surprising because plastic flows in BCC elemental metals and dilute alloys are generally controlled by screw dislocations. We use the insight and theory to perform a computationally-guided search over 107 BCC HEAs and identify over 106 possible ultra-strong high-T alloy compositions for future exploration.
More Related Videos
Related Concept Videos
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
Temperature Dependent Deformation
Hooke's Law
Stress-Strain Diagram - Ductile Materials
Yield Criteria for Ductile Materials under Plane Stress
The Maximum Shearing Stress Criterion, also known as...
Strain-Energy Density
In the elastic region of a material, the relationship between the stress and the strain is linear and follows Hooke's Law. The strain energy density in this...

