Scaling confirmation of the thermodynamic dislocation theory
J S Langer1, K C Le2
1Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106; james.langer@icloud.com lekhanhchau@tdtu.edu.vn.
Summary
The thermodynamic dislocation theory (TDT) successfully predicts material behavior under stress. This validated theory offers new solutions for complex solid mechanics problems involving dislocations.
Area of Science:
- Materials Science
- Solid Mechanics
- Thermodynamics
Background:
- The thermodynamic dislocation theory (TDT) is based on unconventional assumptions about systems with numerous dislocations.
- These assumptions involve the second law of thermodynamics and the rate of dislocation unpinning.
Purpose of the Study:
- To test the validity of the TDT by examining its predictions for steady-state stress.
- To evaluate the TDT's applicability to materials like aluminum and copper.
Main Methods:
- Deriving a scaling relation for steady-state stress based on TDT assumptions.
- Comparing the predicted scaling relation with experimental data for aluminum and copper.
Main Results:
- The TDT accurately predicts a scaling relation between steady-state stress and strain rate.
- This relation holds true across a broad spectrum of experimental data for aluminum and copper.
Conclusions:
- The TDT passes a stringent test, confirming its validity.
- The validated TDT provides a reliable framework for addressing previously intractable problems in solid mechanics.
Keywords:
dislocationseffective temperaturenonequilibrium deformationthermal activationthermodynamicsMore Related Videos
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