Fabrication and Mechanical Properties of Tri‐Layer B4C‐Reinforced Al–Zn Functionally Graded Foam Having Higher Energy Absorption Efficiency

Abstract

Metal foams are lightweight and have a higher impact energy absorption ability, making them suitable for various dynamic load applications. However, thin cell walls having higher porosity and lower compressive strength limit the foam's application. Density‐graded foams have superior compressive properties to uniform foam, making them a suitable lightweight candidate for dynamic loading applications. The tri‐layer functionally graded foam material (FGFM) is fabricated using the hot pressure‐assisted sintering and dissolution route by varying the porosity and B4C reinforcement. The density gradation enhances the load‐bearing capacity compared to uniform foam, and the maximum compressive strength achieved is 142 MPa. Also, the densification strain is 26% higher compared to uniform foam. B4C (9 vol%)‐reinforced FGFM shows the highest energy absorption efficiency of ≈67% due to their stabilized plateau region.