Steel foam: Heat treatment, mechanical and corrosion behavior

Metal foams are a class of materials with extremely low densities and an outstanding combination of mechanical, electrical, thermal, and acoustic properties. They offer a large potential for light-weight structures with high stiffness and high mechanical properties, energy absorption, and thermal management. Their extraordinary property combinations make them interesting for applications where more than one function can be met. Steel foam produced by slip reaction foam sintering process (SRFS) had a chemical composition of 1%C, 1.3 %Mn, 0.5% Si and 0.5 % Cr is subjected to many different heat treatment and corrosion conditions. In the presented work, the effect of different heat treatment conditions was applied to investigate its effect on the mechanical behavior of produced steel foam. Austenizing at 800, 850 and 900 degree Celsius for one hour was applied and tempering at 400, 450 and 500 for one hour respectively was examined. Corrosion characterization for the samples was carried out by using the salt spray test; samples were subjected to marine "corrosive" atmosphere for 54 hours at 40 degrees Celsius and by using the autoclave (high temperature/high pressure) samples were subjected to steam of distilled water at high pressure and high temperature reached 170 degrees Celsius for 96 hours. Compression test was carried out to test and evaluate the mechanical properties for the samples, before and after corrosion tests also before and after heat treatment process. The results showed that corrosion can negatively affects the mechanical properties of the steel foam, as in the compression test the samples which was not subjected to any of the corrosive atmosphere showed much better results than the samples which was tested in the salt spray or the autoclave test. Not only but also heat treatment process showed a great influence on the mechanical behavior of steel foam, as using different heat treatment cycle, better compression stress could be achieved.