Abstract: A ceramic laminate includes a first ceramic layer and a second ceramic layer which are laminated with each other via a bonding layer. The first ceramic layer has gas permeability. The second ceramic layer has gas impermeability. A method for forming this ceramic laminate includes a step of forming first and second ceramic layer forming green sheets, a step of coating a bonding layer forming paste on the second ceramic layer forming green sheet, and a step of integrally bonding the first ceramic layer forming green sheet with the bonding layer forming paste into a laminated body and then sintering the laminated body.

Abstract: A non-sintered element body having a predetermined shape is fabricated from powdery raw material of a solid electrolytic body. The non-sintered element body is temporarily sintered to obtain a partially-sintered element body as a semi-finished product of the solid electrolytic body. An outer surface of the partially-sintered element body is dipped into a slurry. The slurry contains surface roughing powder including large and small grains which are mutually differentiated in grain size. Then, the partially-sintered element body with a rough slurry film coated thereon is completely sintered into the solid electrolytic body.

Abstract: A non-sintered element body having a predetermined shape is fabricated from powdery raw material of a solid electrolytic body. The non-sintered element body is temporarily sintered to obtain a partially-sintered element body as a semi-finished product of the solid electrolytic body. An outer surface of the partially-sintered element body is dipped into a slurry. The slurry contains surface roughing powder including large and small grains which are mutually differentiated in grain size. Then, the partially-sintered element body with a rough slurry film coated thereon is completely sintered into the solid electrolytic body.