Synthesis of syntactic steel foam using gravity-fed infiltration

► Syntactic steel foams produced by gravity-fed infiltration of thin-walled alumina microspheres. ► Relative density of the steel syntactic foams was 0.46. ► Critical parameters were melt temperature, microspheres preheating temperature. ► Syntactic foams candidates for energy absorption applications. ► Syntactic steel expected to show higher strengths than aluminum foams.