The effects of hydrolysis and additive conditions on the gel-to-ceramic conversion of sol-gel derived PbTiO sub 3

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6884189

Schwartz, R W; Lakeman, C D.E.; Payne, D A ^[1]

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1. Illinois Univ., Urbana, IL (USA). Materials Research Lab.

Lead titanate was prepared by sol-gel processing of metal alkoxide solutions. The effects of hydrolysis level (i.e., moles H{sub 2}O/mole PbTiO{sub 3}) and acid and base additives (HNO{sub 3} or NH{sub 4}OH) on desiccated gel properties and the gel-to-ceramic conversion process were studied. The properties of the gels were characterized at three stages of the processing cycle: (1) the desiccated gel state; (2) the amorphous state, following organic pyrolysis; and (3) the crystalline state. Differences in the physical and structural properties of the desiccated gels, induced through manipulation of the hydrolysis conditions, persisted in the amorphous state, i.e,. following organic pyrolysis. Minor differences remained after crystallization. The variation in material properties with low temperature processing (i.e., the gel-to-glass transformation) is considered from the standpoint of the effects of hydrolysis and additive conditions on gel network structure and consolidation behavior. The densification and crystallization behavior of the gels were also characterized. Through proper control of hydrolysis conditions, relatively dense ceramics were obtained at temperatures as low as 700{degree}C.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• Sponsoring Organization: DOE/DP
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6884189
• Report Number(s): SAND-89-3088C; CONF-900466--66; ON: DE90012999
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ADDITIVES
AMORPHOUS STATE
CHEMICAL REACTIONS
COLLOIDS
CRYSTAL STRUCTURE
CRYSTALLIZATION
DECOMPOSITION
DISPERSIONS
GELS
HEAT TREATMENTS
HYDROLYSIS
LEAD COMPOUNDS
LYSIS
MICROSTRUCTURE
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
POROSITY
SOL-GEL PROCESS
SOLVOLYSIS
TITANATES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS