HIGH DENSITY AND SMALL GRAIN SIZE. THE TECHNICAL OBJECTIVE IS THUS TO ACHIEVE THESE REQUIREMENTS THROUGH AN OPTIMIZATION OF POWDER PREPARATION AND FABRICATION.

FOR MOST APPLICATIONS THE BEST MANUFACTURED ALUMINA CERAMIC WILL REQUIRE A COMBINATION OF HIGH PURITY, HIGH DENSITY AND SMALL GRAIN SIZE. THE TECHNICAL OBJECTIVE IS THUS TO ACHIEVE THESE REQUIREMENTS THROUGH AN OPTIMIZATION OF POWDER PREPARATION AND FABRICATION.

AN IMPORTANT REQUIREMENT OF THE WORK WILL BE TO ACCURATELY CONTROL AND OBSERVE THE MICROSTRUCTURE OF SOME WELL CHARACTERIZED TEST SAMPLES PRODUCED BY PRESSING AND SINTERING A SERIES OF GRADED ALUMINA POWDERS. THE TEST PIECES WILL BE SUBMITTED TO MECHANICAL EVALUATION AND THEIR STRENGTH AND FRACTURE PERFORMANCE WILL BE RELATED TO THEIR MICROSTRUCTURE AND DENSITY PROPERTIES AS WELL AS THE FABRICATION ROUTE CHOSEN. FOR SOME SELECTED WEAR APPLICATIONS THE WEAR RESISTANCE UNDER ABRASIVE CONDITIONS WILL BE MEASURED. A LIMITED NUMBER OF ELECTRICAL CONDUCTIVITY AND IMPURITY ASSESSMENT EXPERIMENTS WILL ALSO BE CARRIED OUT ON SAMPLES INTENDED FOR ELECTRONIC SUBSTRATE AND INSULATOR APPLICATIONS.

THIS PROJECT IS A COORDINATED EXERCISE BETWEEN SEVEN PARTICIPANTS:

PRODUITS CHIMIQUES UGINE KUHLMANN (FRANCE) POWDER SUPPLY DEVELOPMENT AND CHARACTERISATION

CERAMICS DEPT., LEEDS UNIVERSITY (UK) LABORATORY-SCALE FABRICATION

ANDERMAN & RYDER (UK)
FELDMUHLE (FRG), SUR-129-D) LARGER-SCALE FABRICATION
GENERAL ELECTRIC COMPANY (UK) PRODUCT EVALUATION
ROYAL WORCESTER INDUSTRIAL CERAMICS (UK)

MATERIALS ENGINEERING CENTRE HARWELL, UK, (SUT-122-UK) WILL ACT AS PROJECT COORDINATOR FOR THE PARTICIPATING UNITS.