Al2O3 Ceramics with Graded Porosity Produced from Natural and Artificial Pore Formers, pages: 595-598
Al2O3 ceramics with graded porosity were produced by using corn starch and PMMA sphere as pore former additives (PFA). Graded porosity was obtained by uniaxially pressing the stacks of Al2O3 mixtures with and without PFA together. Pressed samples were heat-treated to remove PFAs at 600oC and sintered at 1540oC. Final porosity of graded ceramics produced from starch and PMMA were measured as 12 and 16%, obtained median pore size were 3 and 11 µm, respectively. The elastic moduli of the samples were measured by pulse-echo method and results showed that moduli values of the samples varied significantly depending on the PFA type. PMMA added samples had lower elastic moduli values than starch added ceramics as a result of higher pore size and interconnected pore structure. By using the pulse-echo method, the elastic properties of the graded samples couldn’t be measured effectively.
Studart, A.R., Gonzenbach, U.T., Tervoort, E., Gauckler, L.J., “Processing routes to macroporous ceramics: A review”, Journal of the American Ceramic Society, 89 (6): 1771–1789 (2006).
Miao, X., Sun, D., “Graded/gradient porous biomaterials”, Materials, 3: 26-47, (2010).
Tampieri, A., Celotti, G., Sprio, S., Delcogliano, A., Franzese, S., “Porosity-graded hydroxyapatite ceramics to replace natural bone”, Biomaterials, 22: 1365-1370, (2001).
Li, J-F, Takagi, K., Ono, M., Pan, W., Watanabe, R., Almajid, A., Taya, M., “Fabrication and evaluation of porous piezoelectric ceramics and porosity-graded piezoelectric actuators”, Journal of the American Ceramic Society, 86(7): 1094–1098 (2003).
Werner, J., Linner-Kremar, B., Friess, W., Greila, P., “Mechanical properties and in vitro cell compatibility of hydroxyapatite ceramics with graded pore structure”, Biomaterials, 23: 4285-4294, (2002).
Roy, W.R., “Porosity of ceramics”, Marcel Dekker Inc, New York, (1996).
Asmani, M., Kermel, C., Leriche, A., Ourak, M., “Influence of porosity on Young’s modulus and poisson’s ratio in alumina ceramics”, Journal of the European Ceramic Society, 21: 1081-1086, (2001).
Deng, Z-Y, Fukasawa, T., Ando, M., “Microstructure and mechanical properties of porous alumina ceramics fabricated by the decomposition of aluminum hydroxide”, Journal of the American Ceramic Society, 84(11): 2638–2644, (2001).
Topates, G., Eren Gültekin, E., “Sonic characterization of porous Si3N4 produced by various pore formers”, Journal of Achievements in Materials and Manufacturing Engineering, 63: 13-18, (2014).
Medding, J.A.,” Nondestructive evaluation of zirconium phosphate bonded silicon radomes”, Master Thesis, Virginia Polytechnic Institute and State University, (1996).
Kulkarni, N., Moudgil, B., Bhardwaj, M., “Ultrasonic characterization of green and sintered ceramics: I, time domain”, American Ceramic Society Bulletin, 73: 146-153, (1994).
- Şu halde refbacks yoktur.
Politeknik Dergisi © 2014
P-ISSN 1302-0900 E-ISSN 2147-9429