Paper Title:
Nanocomposites – Toughened Ceramics
  Abstract

In order to improve fracture toughness of ceramics, an intrinsically small frontal process zone (FPZ) size must be expanded. An intra-type nano-structure, where nano-particles are embedded within matrix grains, yields dislocations around the dispersed particles due to residual stresses. These dislocations become sessile dislocations at room temperature, operate as origins of small stress concentration in the matrix, and create nano-cracks in the FPZ. To produce the intra-type nano-structure, we developed a soaking method. This method makes it possible to produce nano-sized metallic particles dispersed within ceramic powders. In this research, alumina-nickel nanocomposite powder was obtained using the soaking method. The powder mixed with α-alumina as a seed was sintered using a pulse electric current sintering technique. The sintered nanocomposites are then annealed to disperse dislocations around the nanoparticles into alumina grains. Results showed that the maximum fracture toughness was 7.6 MPam1/2, which was two times higher than that of alumina.

  Info
Periodical
Key Engineering Materials (Volumes 336-338)
Edited by
Wei Pan and Jianghong Gong
Pages
2242-2246
DOI
10.4028/www.scientific.net/KEM.336-338.2242
Citation
H. Awaji, T. Matsunaga, S. M. Choi, "Nanocomposites – Toughened Ceramics", Key Engineering Materials, Vols. 336-338, pp. 2242-2246, 2007
Online since
April 2007
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Dae Joon Kim, Deuk Yong Lee, Jung Suk Han
831
Authors: Oleg Vasylkiv, Yoshio Sakka, Valeriy Skorokhod
2347
Authors: Ke Wang, Pascal Ogier, Chauhari Wuiwui Tjiu, Chaobin He
Abstract:Alumina nano-crystals were dispersed in epoxy resin via different approaches. The effects of filler dispersion on the mechanical properties...
233
Authors: Seong Min Choi, Uraiwan Leela-adisorn, Sawao Honda, Shinobu Hashimoto, Hideo Awaji
Abstract:Intra-type structure of ceramic matrix composites (CMCs) can improve the mechanical properties of ceramic materials. In this work, we used...
115
Authors: Oleg Vasylkiv, Yoshio Sakka, Valeriy Skorokhod
Abstract:The 0.75 to 3 mol% Y2O3-stabilized tetragonal ZrO2 and Al2O3/Y-TZP nano-composite ceramics with 0.2 to 0.7 wt% of alumina were produced by a...
615