Synthesis and Quasi-Static Compressive Properties of Mg-AZ91D-Al₂O₃ Syntactic Foams

Area of Science:

• Materials Science
• Metallurgy
• Mechanical Engineering

Background:

• Magnesium alloys offer lower density than aluminum, enabling higher specific energy absorption in syntactic foams.
• Syntactic foams utilizing magnesium alloy matrices are underexplored despite their potential advantages.
• Hollow ceramic particles are investigated as reinforcement for metal matrix syntactic foams.

Purpose of the Study:

• To investigate the properties of magnesium alloy matrix syntactic foams reinforced with Al₂O₃ hollow particles.
• To determine the effect of hollow particle size and wall thickness on foam performance.
• To evaluate the potential of these foams as lightweight, high-energy absorbing materials.

Main Methods:

• Encapsulation of Al₂O₃ hollow particles (three size ranges) within Mg-AZ91D alloy.
• Utilized a sub-atmospheric pressure infiltration technique for foam fabrication.
• Characterized mechanical properties including peak strength, plateau strength, and toughness.

Main Results:

• Foam strength and toughness increased with higher hollow sphere wall thickness to diameter (t/D) ratio.
• Smaller hollow spheres resulted in increased t/D ratios and improved specific energy absorption.
• The developed magnesium alloy syntactic foams demonstrated superior specific properties compared to other metallic foams.

Conclusions:

• Magnesium alloy syntactic foams with Al₂O₃ hollow particles exhibit enhanced specific energy absorption.
• Optimizing hollow sphere size and t/D ratio is crucial for maximizing performance.
• These advanced materials show promise for applications requiring lightweight and high energy absorption capabilities.