Process for making a piezoelectric body

A process for producing a piezoelectric body which may be polarized in an aligned permanent fashion comprising:

• mixing a select amount of a granular ferroelectric material having a Curie temperature greater than 200.degree. C. with a sufficient amount of a fluidized bonding material to bind said granular ferroelectric material into a cohesive body,
• said bonding material being characterized by a specific conductivity below said Curie temperature of the ferroelectric material in accordance with the formula
• .sigma..sub.B .gtoreq. E.sub.C .times. .sub.K /E.sub.B
• wherein .sigma..sub.B is the specific conductivity of the bonding material;
• E.sub.c is the coercive field strength of the ferroelectric material;
• .sigma..sub.K is the specific conductivity of the ferroelectric material;
• and
• E.sub.b is the electric breakdown field strength of the bonding material;
• shaping said mixture into a solid predetermined body shape;
• heating said solid body to a temperature sufficient to exhibit said specific conductivity in the bonding material but below said Curie temperature of the ferroelectric material;
• and
• applying an electric voltage of sufficient intensity to said heated solid body to produce a permanent polarization alignment in the ferrorelectric material within said solid body but below that required to heat damage the bonding material.