| 摘要 |
PURPOSE:To use a polycrystalline substance for a piezoelectric transducer, for a filter material of an electric signal and for an oscillation element by a method wherein, at a method to manufacture a piezoelectric substance by heating an amorphous substance at its crystallization temperature or higher and at its melting point temperature or lower and by crystallizing a piezoelectric substance phase, the polycrystalline substance whose orientation property is changed continuously in the temperature grade direction is crystallized. CONSTITUTION:For example, in order to crystallize an Li2O.2B2O3 piezoelectric phase having a good temperature characteristic from an Li2O-B2O3-based amorphous material, a batch in which high-purity Li2CO3 and high-purity H3BO3 have been mixed in a target weight ratio is put into a platinum crucible and heated. H2O and CO2 are decomposed. The mixture is held, for at least one hour or higher, at a temperature (1100 deg.C) which is by 200 to 300 deg.C higher than the liquidus of this specimen; it is changed to a uniform molten substance; after that, the substance is injected into a carbon mold; a disk-shaped amorphous material is obtained. The material is annealed at a temperature close to a glass transition temperature for 10 minutes to several hours; a thermal strain in the specimen is removed; after that, the material is polished and cleaned. The produced amorphous material 1 is placed on a hot plate 2 and a crystallization treatment is executed in the air. |
