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Functional Materials Under Stress: In Situ TEM Observations of Structural Evolution
Yu Deng1, Ruopeng Zhang2,3, Thomas C Pekin2,3
1Solid State Microstructure National Key Lab and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.
Advanced Materials (Deerfield Beach, Fla.)
|November 21, 2019
Summary
Mechanical loading induces microstructural changes in functional materials. In situ nanomechanical testing in electron microscopes reveals these evolutions, aiding in property tuning and performance enhancement.
Area of Science:
- Materials Science
- Mechanical Engineering
- Nanotechnology
Background:
- Functional materials undergo structural changes under varying stress fields.
- Mechanical loading can induce complex microstructures (defects, domains, phases) in materials.
- These microstructural changes offer insights into deformation and can be used to tune material properties.
Purpose of the Study:
- To investigate microstructural evolution in functional materials under mechanical loading.
- To demonstrate the utility of in situ nanomechanical testing for studying these changes.
- To highlight the impact of advanced experimental techniques.
Main Methods:
- In situ nanomechanical testing within scanning/transmission electron microscopes (STEM/TEM).
- Observation and analysis of microstructural evolution during mechanical loading.
- Utilizing newly developed multichannel experimental capabilities.
Main Results:
- Mechanical loading induces diverse microstructural features in functional materials.
- In situ TEM/STEM observations reveal the dynamic processes of microstructural evolution.
- Controlled induction of microstructures can enhance material performance.
Conclusions:
- In situ nanomechanical testing is crucial for understanding functional material behavior.
- Microstructural engineering via mechanical loading offers pathways for property optimization.
- Advanced experimental setups enhance the capability to study these phenomena.
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