Metal foams are a cellular structure that has a solid matrix made of metal and has pores in their structure. Metal foams offer excellent combination of properties which led researchers interested in investigation in recent years. Closed-cell stainless steel (SS316L) foams for biomedical application were prepared by space holder method and the physical and morphological properties of SS316L foams were studied. Stainless steel (SS316L) powders as metallic material, polyethylene glycol (PEG) as a binder and Urea as a space holder material were mixed homogenously to avoid the particle wrecked. This mixture was compacted using uniaxial pressing machine and pressurized to 8 tons to formed the green body. By using tube furnace, the SS316L foams was two-stage sintered, the first phase at 600°C for 2 hours to decompose the urea, and the second phase at 1000°C, 1100°C, and 1200°C respectively to sinter the steel. The porosity and density test was carried out by applying Archimedean principles, while morphological observation was done by using Field Emission Scanning Electron (FESEM). The samples with 40wt.% SS316L composition and sintered at temperature of 1100°C, leads to porosities of about 44.539% and show the potential as the best metal foams.

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Recently, there has been renewed interest in fabrication of porous metals and metallic foams as biomedical implants. Metal foams have great properties such high stiffness, great mechanical strength and high energy absorption that cannot be obtained from ceramic and polymer foams. The present study aims to fabricate the porous stainless steel by using urea as space holder material through powder metallurgy technique. Stainless steel (SS316L) powders was used as metallic material were mixed with urea and polyethylene glycol (PEG) as binder using ball milling machine and then compacted at 8 tons. The composition of urea particles into the formulation are 45 wt.%, 50 wt.%, 55 wt.%, and 60 wt.%. The twostages sintering process was performed which at the first stage, the temperature applied was 400 °C for 2 hours to remove the urea particle in the green compacts and the second temperature at 1100 °C for 2 hours to sinter the steel. The characterization of the samples after sintering process was carried out by performing density and porosity test and scanning electron microscopy (SEM) was conducted to identify the morphology characteristic. The findings show that, the sample with 40 wt.% of urea composition produced high density value of about 4.36 g/cm 3. The sample with 60 wt.% of urea composition produced larger pores in their structure and obtained high porosities value of about 56.22%.

Foamed concrete is lightweight concrete formulated from a mixture of concrete mortar and established foam. Generally foamed concrete is known for its low engineering properties. Many researchers had conducted studies and more focused on the physical and mechanical properties of foamed concrete without taking into account the behavior on its fracture energy. Therefore, this study was carried out to investigate the effect of notch-to-depth ratio on fracture energy of foam concrete using three point bending testmethod. Beam specimens with V-notch were prepared at a densityof 1400kg/m3 and 1600kg/m3. Three different notch-to-depth ratios which were adopted at 0.1, 0.3 and 0.5. Fracture energy was determined using Hillerborg, Bazant and Comitee euro International du Beton (CEB) models. From the experimental results, it was shown that fracture energy decreases asthe notch-to-depth ratio increases.

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