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

Conference · Thu Dec 31 23:00:00 EST 1981

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
• Country of Publication: United States
• Language: English

Related Subjects

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