Mechanical behavior of ZrO/sub 2/ toughened Al/sub 2/O/sub 3/

Conference · Fri Jan 01 00:00:00 EST 1982

OSTI ID:5369435

Becher, P F

Recent studies on mechanisms to increase the critical fracture toughness (K/sub IC/) of ceramics have led to the development of high tensile strength (up to 1000 MPa, approx. 150,000 psi as measured in a four-point flexure test) Al/sub 2/O/sub 3/-ZrO/sub 2/ composite materials with high K/sub IC/ values (8 to 13 MPa m/sup 1/2/). These toughness levels are two- to three-fold greater than those of the toughest conventional ceramics. In addition these composites exhibit much better resistance to static fatigue than do alumina ceramics. (< 1 ..mu..m) tetragonal ZrO/sub 2/ particles partially stabilized with Y/sub 2/O/sub 3/ in a polycrystalline ceramic matrix (e.g., alumina). The processing of such composite ceramics utilizes sol-gel techniques which allows one to obtain a much more uniform dispersion of very fine (submicron) second phase particles as well as to control both the grain size and compositional uniformity of the ceramic. Experimental toughening results show that compositional control and microstructure are critical to the extent of increased toughening that can be achieved.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5369435
• Report Number(s): CONF-821268-1; ON: DE84004677
• Resource Relation: Conference: Tokyo Institute of Technology symposium on zirconia ceramics, Yokohama, Japan, 7 Dec 1982
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
FRACTURE PROPERTIES
COMPOSITE MATERIALS
ZIRCONIUM OXIDES
DISPERSIONS
PARTICLES
SOL-GEL PROCESS
ALUMINIUM COMPOUNDS
CHALCOGENIDES
MATERIALS
MECHANICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
360203* - Ceramics
Cermets
&amp; Refractories- Mechanical Properties