PHYSICAL AND ELECTRICAL PROPERTIES OF HOT-PRESSED CERAMICS

Technical Report · Tue Jan 01 04:00:00 EST 1963

OSTI ID:4663096

Haertling, G H

An experimental procedure was developed to hot-press ceramic compositions under a wide range of temperature, time and pressure conditions. A typical member of the lead zirconate-lead titunate-lead stannate family developed by Clevite Corporation was chosen for the experiment, so that the effects of hot- pressing could be observed on ferroelectric properties as well as on other common physical properties of ceramics. Temperature was varied from 1050 to 1400 deg C, time (at temperature) from one minute to twelve hours, and pressure from 1500 to 12,000 psi. Significant improvements in properties were noted for the hot- pressed specimens in comparison to the normally sintered material. Selection of the proper hot-pressing conditions resulted in a general improvement of all the commonly investigated ceramic properties, such as increased remanent polarization, squareness ratio (P/sub r//P/sub s/), planar coupling coefficient and translucency, and a decreased coercive field. Dielectric constant, tangent delta , and thernaal expansion remained unchanged by hot-pressing. A study of the specimen microstructures showed that the final grain size could be varied by alteration of the hotpressing conditions or by addition of small amounts of foreign ions to the base composition. Results indicated a dependence of remanent polarization on average grain size. Bulk densities as high as 99.75% theoretical were obtained by hot-pressing. (auth)

• Research Organization: Sandia Corp., Albuquerque, N. Mex.
• DOE Contract Number: AT(29-1)-789
• NSA Number: NSA-17-036205
• OSTI ID: 4663096
• Report Number(s): TID-17858; SCDC-2951
• Country of Publication: United States
• Language: English

Related Subjects

CERAMICS
COMPACTING
DENSITY
ELECTRICITY
FERROMAGNETIC MATERIALS
GRAIN SIZE
HIGH TEMPERATURE
HOT WORKING
LEAD OXIDES
MECHANICAL PROPERTIES
METALS, CERAMICS, AND OTHER MATERIALS
POLARIZATION
PRESSURE
SINTERED MATERIALS
TEMPERATURE
TENSILE PROPERTIES
TIN OXIDES
TITANIUM OXIDES
ZIRCONIUM OXIDES