Innovative compound casting technology and mechanical properties of steel matrix syntactic foams

In recent years, metal matrix syntactic foams have drawn great attention for its benefits, such as lightweight and energy-absorbing characteristics, of being used as the material of packaging, armors and vehicles. In this paper, a novel compound casting technology is developed to produce steel matrix syntactic foams, which brings in hollow Al2O3 spheres with outer diameters of about Ø3.11mm, Ø3.97mm and Ø4.79mm to make three foams of different densities. Then, the internal microstructure of one produced sample is investigated with X-ray micro-computed tomography. Besides, the quasi-static compressive properties and the deformation characteristics of the three samples are studied with a WAW-1000 testing machine. At last, the relationship between the relative plateau stress and the relative density of the foams is explored and described.