Articles
  • Fabrication and mechanical properties of fibrous silicon nitride monolithic ceramics
  • Hai Guo, Dae-Hyun Yoona and Dong-Woo Shina,*
  • Department of Materials Science and Engineering, Division of Ceramics, Tsinghua University, Beijing, 100084 China a Ceramic Matrix Composites (CMCs) Lab. Division of Materials Science and Engineering, Engineering Research Institute, Gyeongsang National University, Jinju, Gyeongnam 660-701, Korea
Abstract
Fibrous Si3N4 monolithic ceramics with a hexagonal cell (Si3N4 fiber) and diameters in the range of 0.1-0.5 mm were processed using a composite fabrication method with a high preferred orientation by the tape casting of seeds of rodlike beta-Si3N4 single crystals. The densified Si3N4 fibrous monolith showed a fracture toughness of 17 MPa(.)m(1/2) and a three-point bend strength of 690 MPa. The application of reinforcement with SiC whiskers exhibited a fracture toughness (24 MPa(.)m(1/2)) and strength (705 MPa). Grain orientation, interface, and reinforcement played a deciding role in mechanical properties of these monolithic ceramics.

Keywords: Fibrous Si3N4, Fracture toughness, SiC whisker, Grain orientation

This Article

  • 2005; 6(4): 321-325

    Published on Dec 30, 2005

Correspondence to

  • E-mail: