Quantitative Shape-Classification of Misfitting Precipitates during Cubic to Tetragonal Transformations: Phase-Field
Yueh-Yu Lin1, Felix Schleifer1, Markus Holzinger1
1Metals and Alloys, University of Bayreuth, Prof.-Rüdiger-Bormann-Straße 1, 95447 Bayreuth, Germany.
Materials (Basel, Switzerland)
|April 3, 2021
Summary
Precipitate shape significantly impacts metallic alloy strengthening. This study quantifies precipitate shapes in Ni-based and Al-Cu alloys using experiments and simulations, validating a new shape analysis method.
Area of Science:
- Materials Science
- Metallurgy
- Computational Materials Science
Background:
- Precipitation strengthening is key to metallic alloy performance.
- Precipitate shape and evolution critically influence strengthening mechanisms.
- Understanding precipitate morphology is essential for alloy design.
Purpose of the Study:
- To investigate the shape formation and evolution of tetragonal precipitates in metallic alloys.
- To develop and apply a consistent method for quantifying precipitate shapes.
- To compare experimental observations with phase-field simulation results.
Main Methods:
- Utilized phase-field simulations and experimental analysis.
- Employed the method of invariant moments for shape quantification.
- Proposed generalized aspect ratio and normalized λ₂ measures for shape analysis.
Main Results:
- Good agreement was found between simulated and experimental aspect ratios for γ'' precipitates in Ni-based alloys.
- A novel method accurately reproduced experimentally observed in-plane precipitate shapes.
- The study provides quantitative measures for precipitate shape deviations.
Conclusions:
- The developed shape quantification method is effective for analyzing precipitates in metallic alloys.
- Phase-field simulations can accurately predict precipitate shape evolution.
- Accurate shape analysis is crucial for optimizing precipitation strengthening in alloys.
Keywords:
Al-Cu alloymisfitting precipitatenickel-base alloyphase-field simulationprecipitate shapeγ″ phaseθ′ phaseMore Related Videos
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