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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Geometric thermodynamics of strain-induced crystallization in polymers
Sanhita Das1,2, Asif Raza1, Debasish Roy1,2
1Computational Mechanics Laboratory, Department of Civil Engineering, Indian Institute of Science, Bangalore 560012, India.
Physical Review. E
|August 17, 2022
Summary
This study applies Riemannian geometry to nonequilibrium thermodynamics, revealing spurious energy in polymers during strain-induced crystallization. Understanding this curvature helps correct thermodynamic stresses.
Area of Science:
- Thermodynamics
- Polymer Physics
- Differential Geometry
Background:
- Classical fluctuation theory uses Gaussian approximations.
- Ruppeiner introduced Riemannian geometry with an entropic metric.
- Riemannian curvature reveals molecular interaction information in systems.
Purpose of the Study:
- Examine Riemannian curvature implications in slow nonequilibrium thermodynamic systems.
- Investigate strain-induced crystallization in polymers.
- Identify and address spurious energy components.
Main Methods:
- Applied Riemannian geometry and entropic metric to a nonequilibrium polymer system.
- Utilized the local equilibrium hypothesis.
- Analyzed curvature's role in identifying spurious isochoric energy.
Main Results:
- Riemannian curvature provides information on spurious isochoric energy in polymers.
- This energy arises from conformational stretching of crystallized segments.
- Curvature-linked thermodynamic state determines isochoric stretch and spurious energy.
Conclusions:
- The study determines the isochoric stretch in the polymer system.
- A method is proposed to remove spurious free energy for accurate stress recovery.
- Riemannian geometry offers insights into complex thermodynamic phenomena.
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