In this research, feasibility of producing A356 Aluminium open cell foams by infiltration of removable performs made of spherical salt grains was investigated. For this purpose, four different ways for producing spherical salt grains were investigated. Heating the salt grains in copper tubes coated with a refractory material was recognized as the most appropriate method. The results showed that sphericity of salt grains increased first with increasing the soaking temperature at a given time or increasing the soaking time at a given temperature, but decreased after a critical soaking temperature or time. This was due to crystallization tendency of the salt grains at higher soaking temperatures and times. Therefore, 760?C and 6 hours were selected as the appropriate soaking temperature and time, respectively. Preforms made from the spherodized salt grains were then infiltrated with the molten aluminium alloy using gas pressure infiltration method. Effective parameters on fabrication of A356 aluminium open cell foams by infiltration method were investigated and suitable parameters were selected. Not sintering the performs, addition of about 3% magnesium to the melt, machining grooves on the bottom surface of aluminium ingots, covering the top surface of performs with SiC particles and coating the mold surface with a supersaturated mixture of salt water and HOL COTE-110Z commercial coating helped complete and uniform filling of the performs. The optimum infiltrating temperature was selected as 680 ?C. Furthermore, the effect of applied pressure on filling of the performs and mechanical properties of the final foams was investigated. It was observed that with increasing the infiltration pressure, relative density, compressive strength, yield strength and elastic modulus of the produced foams increased and reached to 0.42, 87 MPa, 12 MPa and 0.2 GPa, respectively, for the applied pressure of 10 bar. The average cell diameter and wall thickness of the foam produced at this pressure were 698 and 136 ?m, respectively. Furthermore, the effect of pressure on mechanical properties of the final foam was modeled. Modeling was started by removing spherical voids from a given volume of metal. This was achieved by linking a program written in MATLAB software to CATIA commercial software. The effect of infiltration pressure on the mechanical properties was then investigated using ABAQUS finite element software. The simulation results were in good agreement with the experimental results and the simulation discrepancy for foams with 74.08% and 58.06% porosity was 11.07% and 13.56%, respectively.
