Fabrication of Toughened Alumina Nanocomposites Using γ-Alumina Powder

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To improve fracture strength and fracture toughness in ceramic materials, we focused our attention on an intra-type structure of nanocomposites. We proposed new processing method for fabricating intra-type nanocomposites. In this work, Al2O3/Ni nanocomposites were fabricated using a soaking method and sintered by PECS(Pulse Electric Current Sintering) method. We also estimated seed effects on this system. Seeded nanocomposites showed high fracture strength and higher fracture toughness than non-seeded nanocomposites and monolithic alumina. The fracture strength of the seeded nanocomposites was more than 800MPa in all sintering temperature range. The maximum value of the fracture toughness was 5.5 MPa⋅m1/2 for the specimen sintered at 1350°C. The sintered specimens with high fracture strength and high fracture toughness were annealed from 800°C to 1000°C for 0 to 10 min. The specimen annealed at 800°C for 5 min showed the highest fracture toughness of 7.6 MPa⋅m1/2. This value is two times higher than that of the monolithic alumina.

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Periodical:

Advanced Materials Research (Volumes 11-12)

Main Theme:

Edited by:

Masayuki Nogami, Riguang Jin, Toshihiro Kasuga and Wantai Yang

Pages:

583-586

DOI:

10.4028/www.scientific.net/AMR.11-12.583

Citation:

S. M. Choi et al., "Fabrication of Toughened Alumina Nanocomposites Using γ-Alumina Powder", Advanced Materials Research, Vols. 11-12, pp. 583-586, 2006

Online since:

February 2006

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Price:

$35.00

[1] B. Harris, S.E. Dorey and R.G. Cooke: Composite. Sci. Tech. Vol. 31 (1988), p.121.

[2] W.J. Clegg, K. Kendfall, N. McN. Alford and J.D. Birchall: Nature Vol. 347 (1990), p.455.

[3] K. Niihara: J. Ceram. Soc. Jpn. Vol. 99 (1991), p.974.

[4] H. Awaji, S-M. Choi and E. Yagi: Mech. Mater. Vol. 34 (2002), p.411.

[5] S-M. Choi and H. Awaji: Sci. Tech. Adv. Mater. Vol. 6 (2005), p.2.

[6] H. Awaji and Y. Sakaida: J. Am. Ceram. Soc. Vol. 73 (1990), p.3522. 0 5 10.

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[8] 0 � before annealing � annealed at 800 � � annealed at 900 � � annealed at 1000 � Fracture toughness /MPam 1/2 Fracture toughness /MPam 1/2 Annealing time / min 0 5 10.

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[8] 0 � before annealing � annealed at 800 � � annealed at 900 � � annealed at 1000 � � before annealing � annealed at 800 � � annealed at 900 � � annealed at 1000 � Fracture toughness /MPam 1/2 Fracture toughness /MPam 1/2 Annealing time / min Fig. 6. Fracture toughness of Al2O3/Ni nanocomposites annealed at various conditions. 1200 1300 1400 1500 1600 2 3 4 5 Fracture toughness / MPam 1/2 Sintering temperature / � Fig. 5. Fracture toughness of sintered Al2O3/Ni nanocomposites. � non-seed nanocomposites � seeded nanocomposites � monolithic alumina.

DOI: 10.4271/ams5867a

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