here have shown that beyond these values (>15 % of the Glass Bubbles) the effect is a decrease in ductility; the material become brittle at the higher percentages of this kind of additive. 2.4 Conclusion In the present work, a simple idea was developed on the production of sponge composites by using a low cost method (mixture of aluminum matrix with organic sugar admixing micro hollow glass bubbles and cold pressing + sintering). Results obtained so far indicates that the method is quite promising in producing foams with open, interconnected cells (sponges) as a result of volatilization of sugar granulates, and glass spheres as closed cells. Acceptable dispersion of both open spaces and closed cells can be achieved when proper mixing/pre-compacting conditions are employed. Product shows low density (relative density around) and ability of energy absorption in impacts. Results also showed that the two parameters investigated—addition or not of Glass Bubbles and type of sugar granulate (white sugar, fine dimension or Brown Sugar, coarse dimension) presented no conclusive effect on the density and compression behavior of the products. The addition of Glass Bubbles tend to promote decrease in density and to increase plastic deformation of the material (for GB contents up to 15 %). As a general conclusion, this preliminary study indicates that the technique of producing porous metals containing both open and closed cells, using sugar as space holder for the first and hollow glass spheres for the second, by means of sintering, is worthy investigating. References 1. Slipenyuk A, Kuprin V, Milman Y, Goncharuk V, Eckert J (2006) Properties of P/M processed particle reinforced metal matrix composites specified by reinforcement concentration and matrix-to-reinforcement particle size ratio. Acta Mater 54(1):157–166 2. Irot FA, Queniss JM, Naslain R (1987) Discontinuously reinforced aluminum matrix composites. Compos Sci Technol 30:155–163 3. Torralba JM, daCost CE, Velasco F (2003) P/M aluminum matrix composites: an overview. J Mater Process Technol 133(1–2):203–206 4. Dasgupta R (2012) Aluminum alloy-based metal matrix composites: a potential material for wear resistant applications, International Scholarly Research Network. ISRN Metallurgy 2012:14 pp. doi:10.5402/2012/594573, Article ID 594573 5. Massol M, Gargiulo J, Gatamorta F (2014) Development of low cost aluminum based composites reinforced with light organic materials and oxides. Final research project (PSYN-2014), Supmeca/LISMMA—Paris, Mechanical and Manufacturing Engineering, Paris—France, 35 pp 6. Ferreira L-P (2013) Production of aluminum metal matrix composites by thixoforming of recycled chips. Thesis for Master of Science, University of Campinas, UNICAMP, Mechanical and Manufacturing Engineering, Campinas—SP, Brazil 7. Robert MH, Jorge AF (2012) Processing and properties of AA7075/porous SiO2–MgO–Al2O3 composite. JAMME 3:1–5 Table 2.4 General mechanical characteristics of the produced foams, obtained in semi-static compression tests Sample Modulus (MPa) Load at offset yield (N) Stress at offset yield (MPa) Load at yield (N) Stress at yield (MPa) Peak load (N) Peak stress (MPa) WS30 243.245 14,194.25 32.72 18,140.73 41.82 19,296.26 44.48 WS30GB10 243.245 14,194.25 32.72 18,140.73 41.82 19,296.26 44.48 BS30 415.947 20,648.17 50.57 ‐ ‐ 39,834.89 97.56 BS30GB10 261.204 13,514.68 32.52 ‐ ‐ 18,674.45 44.94 2 Preliminary Study on the Production of Open Cells Aluminum Foam by Using Organic Sugar as Space Holders 13
RkJQdWJsaXNoZXIy MTMzNzEzMQ==