Manufacturing and Characterization of Open-Cell Aluminum Foam Produced via Infiltration of Leachable Space Holder

Abstract

Open-cell Al-Si foam samples were produced using infiltration casting technique. The metal infiltration process was performed in a specially designed and built setup consisting of a vertical chamber resistance furnace, a pressurization chamber connected to an Argon gas cylinder through a control manifold. To control the relative density of the produced foams, non-compacted and compacted preforms (5 MPa) were prepared from 2 or 4 mm NaCl particles. The compaction was performed using a hydraulic press in the same infiltration chamber. Argon pressure of 3 bars was applied to infiltrate the preforms with the aluminum alloy after melting at 750 °C. The produced aluminum foam specimens show no lack of filling, a high degree of preform replication, and good homogeneity of pore sizes. The preliminary physical and mechanical characterization tests, including relative density, plateau stress, densification strain, and elastic modulus of the foam, are comparable to the values reported in previous investigations, in which more complicated, time-consuming, higher energy, and costly techniques were used. Further investigations on wider ranges of particle sizes, compaction, and infiltration pressures are currently in progress.