Dislocation Entropy: Temperature and Density Dependence

TL;DR

This paper investigates dislocation entropy in metals under laser shock peening, analyzing how temperature and density influence defect dynamics and material hardening through a combined combinatorial and physical oscillator approach.

Contribution

It introduces a novel analysis of dislocation entropy considering both combinatorial and physical oscillator perspectives, advancing understanding of defect dynamics in metal hardening.

Findings

Dislocation entropy depends on temperature and density.

The combined model describes free energy of dislocation ensembles.

Insights into defect dynamics improve material hardening understanding.

Abstract

Laser hardening of metals occurs under the influence of a shock wave, which changes the distribution and density of one-dimensional defects - dislocations. There is a relationship between the density of dislocations, the grain size and the resistance of a single crystal to shear loading. The mechanism of hardening processes continues to be intensively studied, and the dynamics of defects plays a central role here. In this paper, the dislocation entropy is analyzed from a combinatorial point of view and from the point of view of a physical oscillator with a given energy reserve. Both contributions play an important role in describing the free energy of a one-dimensional ensemble of dislocations, and are necessary to take into account the dynamic processes inside the grain of a polycrystalline structure. Keywords: Laser Shock Peening, statistical mechanics