To produce a dense piezo electric ceramic reduced in pores by suppressing vaporization of PbO in a firing process in the production of a multicomponent piezo electric ceramic consisting essentially of PbO.
Substitution for firing atmospheric gas is conducted for at least 3 times. The firing process is divided into 3 steps and as the 1st step, the oxygen partial pressure in the firing atmosphere in a temp. range, where the shrinkage factor of the ceramic is ≤5%, is controlled to 0.1-0.5. As the 2nd firing step, the oxygen partial pressure of the firing atmosphere in a temp. range, where the shrinkage factor of the ceramic is 5-10% and the pore of ceramic is opened to the outside atmosphere, is controlled to 0.2-1.0. As the 3rd step, the oxygen partial pressure of the firing atmosphere in a temp. range, where the shrinkage of the ceramic is 10-25% and the pore of the ceramic is closed to the outside atmosphere, is controlled to 0.1-0.5. Thus, the more dense ceramic sintered compact than that in the case of a conventional atmospheric firing is produced.
| WO/1988/006575 | PROCESS FOR THE PREPARATION OF ALUMINIUM OXIDE CERAMICS HAVING INCREASED ABRASION RESISTANCE |
| JPS62105964 | MANUFACTURE OF CERAMICS |
| WO/2006/134673 | PROCESS FOR PRODUCING CERAMIC SHEET |
SHIOYA KAZUHIDE
HASHIMOTO EMIKO
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