Quantifying the Relationship between Structure and Yield Stress in the Evolution of Aluminum Foam

This study explores an extension of the scaling law to enhance the prediction accuracy of yield stresses in aluminum foam. To complete that, the series of aluminum foam samples are prepared via the melt foaming method with different holding periods. After that, the porous structure information is obtained in terms of X‐ray computed tomography (CT) scanning. During the sample preparation process, the pore structure undergoes a “merging point,” where the numerous small pores transition to large pores with reduced sphericity. The incorporation of additional five parameters (relative density, diameter, solid material thickness, anisotropy, and sphericity) into the expanded law of proportions significantly improves the residual value R² of the predicted results, increasing from 0.7251 in the Gibson–Ashby equation to 0.8926. Additionally, after eliminating redundant parameters through stepwise linear regression, the simplified equation still achieves a residual value R² of 0.8699. The remaining structural parameters, including porosity, sphericity, solid material thickness, and anisotropy, independently are found to have an influence on the yield stress through covariance analysis. By correlating these processes, it is expected that the mechanical properties of aluminum foam can be precisely regulated by adjusting the parameters.