27-11-2012, 01:29 PM
PIEZOELECTRIC CERAMICS
ceramics.ppt (Size: 133 KB / Downloads: 33)
BATCH PREPARATION & 1st MILLING
The raw materials & additives are accurately weighed
milled by the wet grinding process
the paricle size is reduced
CALCINATION
The material is loaded in alumina crucibles
calcined at a temp. of about 1000 c for a specified time
initial solid state reaction takes place with the partial formation of lead zirconate titanate
second MILLING
The calcined material is crushed with a ceramic pastle
loaded into the rubber lined jars
placed on a roller mill & milled for a standardised time
GRANULATION
The process is carried out to have material in the free flowing form of soft round globules
hence ,proper packing density during pressing
impart great strength
ELECTRODING
A conducting thick film of silver is deposited on both sides of the crystals
Three electroding methods can be used:-
Vacuum deposition method
screen printing method
by brushing using a silver paste