Compressive Properties of Aluminum Matrix Syntactic Foams Prepared by Stir Casting Method

Abstract

Aluminum matrix syntactic foams with the density of 1.68–2.05 g cm−3 are prepared by the stir casting method. Al2O3 hollow spheres with a volume fraction of 38–48% are chosen as reinforcement and their diameters had three ranges. Ca particles increased melt viscosity to ensure uniform dispersion and good interfacial wettability of the hollow spheres in matrixes. Quasi‐static compression tests are performed. The results show that the mechanical properties and energy absorption capacity increased with decreasing size of the hollow spheres and increasing density of syntactic foams. For the same size hollow spheres and the same density gradient, the T6‐ZL111 matrix syntactic foams had the highest properties, while the cpAl matrix syntactic foams had the lowest values. Macroscopically, relative to plastic collapse, brittle fracture of syntactic foams dominated in compression process. The microscopic deformation and failure mechanism related to matrix plasticity, heat treatment, and density of syntactic foams.