Study of dynamic grain growth by electron microscopy and EBSD.

Area of Science:

• Materials Science
• Metallurgy
• Physical Metallurgy

Background:

• Aluminum-copper alloys with varying CuAl(2) volume fractions exhibit Zener pinning and distinct superplastic properties.
• Understanding the impact of hot deformation on these microstructures is crucial for optimizing material performance.

Purpose of the Study:

• To investigate the effects of hot deformation on the microstructure of aluminum-copper alloys.
• To quantitatively analyze strain-induced grain growth and compare it with static grain growth.
• To elucidate the mechanisms driving microstructural changes during deformation.

Main Methods:

• In situ scanning electron microscopy (SEM) hot deformation experiments.
• Electron backscatter diffraction (EBSD) for microstructural analysis.
• Surface marker observations and secondary/backscattered electron imaging.

Main Results:

• Strain-induced grain growth was observed in both Al-4wt%Cu and Al-33wt%Cu alloys.
• Grain boundary motion during deformation resulted in layered structures, with some grains increasing and others decreasing in size.
• Challenges were noted in applying EBSD to the superplastic Al-33wt%Cu alloy during deformation.

Conclusions:

• Hot deformation significantly alters the microstructure of aluminum-copper alloys through strain-induced grain growth and grain boundary motion.
• The observed microstructural evolution impacts the superplastic behavior of these Zener pinned systems.
• Further investigation into EBSD application in complex superplastic alloys is warranted.