Statistical mechanics, entropy and temperature analog of dislocations moving on fluctuating resistance landscapes
Source abstract
Abstract
High/medium-entropy alloys, also known as complex concentrated alloys (CCAs), are so called because the mixing entropy reaches a maximum when the constituent multi-elements adopt equiatomic ratios. However, the mixing entropy relates little to mechanical strength for which these alloys are most studied. By analyzing dislocations in VCoNi via electron microscopy and molecular-dynamics from a machine interatomic potential, their energies are found to obey a maximum-entropy distribution in the random alloy state, but not in the annealed state where local chemical order (LCO) exists. The maximum-entropy distribution is characterized by an athermal, mechanical analog of temperature which relates directly to the alloy strength and dominates over the real temperature over a wide range. The entropy of dislocations is a fingerprint of LCO, and statistical mechanics is an impeccable theoretical framework for understanding dislocations and strength in CCAs.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Microstructure and mechanical properties · Thermal properties of materials · Force Microscopy Techniques and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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