Aluminum Foam Sandwich: Pore Evolution Mechanism Investigation and Engineering Preparing Optimization

Area of Science:

• Materials Science and Engineering
• Metallurgy
• Foam Material Characterization

Background:

• Aluminum foam sandwiches (AFS) are advanced materials with unique properties.
• Understanding pore evolution is critical for optimizing AFS production and performance.
• Controlling microstructure and defects is essential for large-scale manufacturing.

Purpose of the Study:

• To investigate the mechanisms of pore evolution in Al-Si-Mg-Cu alloy within AFS.
• To explore cavity design and plate type control for large-scale AFS production.
• To analyze the impact of precursor heating stages on pore formation and AFS properties.

Main Methods:

• Integration of heating-expansion ratio curves and in situ synchronous radiation observation.
• Microscopic analysis of matrix microstructure at various stages of pore evolution.
• Evaluation of edge sealing techniques using square tubes for AFS panel production.

Main Results:

• Precursor heating identified in three stages: rapid heating, solid-liquid transition, and stable foaming.
• Pore nucleation occurs as crack-like structures along the rolling direction, influenced by Mg-enriched regions.
• Edge sealing effectively creates a dense edge zone, halting crack propagation and improving panel flatness.

Conclusions:

• Pore evolution in AFS is a multi-stage process influenced by heating dynamics and material composition.
• Specific pore nucleation and growth mechanisms were elucidated.
• Edge sealing is a viable strategy to mitigate boundary effects and enhance the quality of large-scale AFS panels.