A method for drying at least one unfired columnar honeycomb formed body comprising a raw material composition containing at least one raw material of ceramics, water and at least one heat-gelling binder, and cells defined by partition walls comprising flow paths from a first end surface to a second end surface. The method comprising drying the honeycomb formed body by passing hot gas satisfying 0.8≤T2/T1≤3.3, where T1 represents a gelation temperature of the binder (° C.) and T2 represents a wet-bulb temperature of the hot gas (° C.) through the flow paths from the first end surface and out the second end surface, while surrounding the honeycomb formed body with a correction mold to correct the shape of the honeycomb formed body during drying.

A method for drying at least one unfired columnar honeycomb formed body comprising a raw material composition containing at least one raw material of ceramics, water and at least one heat-gelling binder, and cells defined by partition walls comprising flow paths from a first end surface to a second end surface. The method comprising drying the honeycomb formed body by passing hot gas satisfying 0.8≤T2/T1≤3.3, where T1 represents a gelation temperature of the binder (° C.) and T2 represents a wet-bulb temperature of the hot gas (° C.) through the flow paths from the first end surface and out the second end surface, while surrounding the honeycomb formed body with a correction mold to correct the shape of the honeycomb formed body during drying.

A preparation method of an alumina ceramic valve core ceramic chip and a product thereof. The alumina ceramic valve core ceramic chip is obtained by the steps of mixing alumina, a sintering aid and a toughening agent according to a raw material ratio, ball-milling, drying, cold isostatic pressing, sintering and the like. The alumina ceramic valve core ceramic chip is prepared by adopting nano alumina and zirconium oxide as the sintering aid, so that the material has excellent bending strength, fracture toughness, hardness and low wear rate, the bending strength can reach 357.8-360.06 MPa, the fracture toughness is 4.32-4.56 MPa.sup.1/2, the Vickers hardness is 1592.7-1614.8 MPa, the wear rate is 0.04-0.09%, and the alumina ceramic valve core ceramic chip is an ideal material for preparing a faucet valve core.

A preparation method of an alumina ceramic valve core ceramic chip and a product thereof. The alumina ceramic valve core ceramic chip is obtained by the steps of mixing alumina, a sintering aid and a toughening agent according to a raw material ratio, ball-milling, drying, cold isostatic pressing, sintering and the like. The alumina ceramic valve core ceramic chip is prepared by adopting nano alumina and zirconium oxide as the sintering aid, so that the material has excellent bending strength, fracture toughness, hardness and low wear rate, the bending strength can reach 357.8-360.06 MPa, the fracture toughness is 4.32-4.56 MPa.sup.1/2, the Vickers hardness is 1592.7-1614.8 MPa, the wear rate is 0.04-0.09%, and the alumina ceramic valve core ceramic chip is an ideal material for preparing a faucet valve core.

The present invention relates to a saggar for firing an active material of a secondary battery, a method for manufacturing the saggar, and a method for firing the active material. The saggar for firing an active material of a secondary battery according to the present invention has a coating layer formed on a bottom surface or a wall surface thereof so as to collect carbon dioxide. By means of the coating layer, the concentration of the carbon dioxide in the saggar can be lowered by collecting the carbon dioxide that is a by-product resulting from a firing reaction, thereby enabling a reduction in the amount of remaining lithium in the active material. The saggar of the present invention provides the saggar for firing an active material of a secondary battery, wherein the saggar has at least one through hole in the bottom surface, or the bottom surface and wall surfaces thereof so as to communicate a gas.

The present invention relates to a saggar for firing an active material of a secondary battery, a method for manufacturing the saggar, and a method for firing the active material. The saggar for firing an active material of a secondary battery according to the present invention has a coating layer formed on a bottom surface or a wall surface thereof so as to collect carbon dioxide. By means of the coating layer, the concentration of the carbon dioxide in the saggar can be lowered by collecting the carbon dioxide that is a by-product resulting from a firing reaction, thereby enabling a reduction in the amount of remaining lithium in the active material. The saggar of the present invention provides the saggar for firing an active material of a secondary battery, wherein the saggar has at least one through hole in the bottom surface, or the bottom surface and wall surfaces thereof so as to communicate a gas.

Provided are a method of manufacturing a ceramic article including a porous portion in which improvement in mechanical strength of a modeled article is achieved while high modeling accuracy is obtained, and a ceramic article. The method of manufacturing a ceramic article includes the steps of: (i) irradiating powder of a metal oxide containing aluminum oxide as a main component with an energy beam based on modeling data to melt and solidify or sinter the powder, to thereby form a modeled article including a porous portion; (ii) causing the modeled article formed in the step (i) to absorb a liquid containing a zirconium component; and (iii) heating the modeled article that has absorbed the liquid containing the zirconium component, wherein, in the absorbing step, the liquid is absorbed so that a ratio of the zirconium component in a metal component contained in the porous portion becomes 0.3 to 2.0 mol %.

Provided are a method of manufacturing a ceramic article including a porous portion in which improvement in mechanical strength of a modeled article is achieved while high modeling accuracy is obtained, and a ceramic article. The method of manufacturing a ceramic article includes the steps of: (i) irradiating powder of a metal oxide containing aluminum oxide as a main component with an energy beam based on modeling data to melt and solidify or sinter the powder, to thereby form a modeled article including a porous portion; (ii) causing the modeled article formed in the step (i) to absorb a liquid containing a zirconium component; and (iii) heating the modeled article that has absorbed the liquid containing the zirconium component, wherein, in the absorbing step, the liquid is absorbed so that a ratio of the zirconium component in a metal component contained in the porous portion becomes 0.3 to 2.0 mol %.

A process for marking a surface of a refractory ceramic part, known as the “surface to be marked.” The part has a microstructure of grains including more than 50% by mass of ZrO.sub.2, bound by a silicate binder phase, and a total porosity of less than 5% by volume. The process involves irradiation of the surface with a laser beam. The beam is emitted by a laser device set to comply with relationship: a.V.sup.2+b.F.sup.2+c.VF+d.V+e.F+f<0, in which: a=10.sup.4.D+2×10.sup.6, b=0.5×10.sup.6.D−150×10.sup.6, c=0.5×10.sup.6.D−300×10.sup.6, d=5×10.sup.3.D−2.5×10.sup.6, e=−5×10.sup.3.D+2.0×10.sup.6, and f=−5×10.sup.9.D+1.8×10.sup.12. V is expressed in mm/second, D is expressed in mm and F is expressed in kHz.

A process for marking a surface of a refractory ceramic part, known as the “surface to be marked.” The part has a microstructure of grains including more than 50% by mass of ZrO.sub.2, bound by a silicate binder phase, and a total porosity of less than 5% by volume. The process involves irradiation of the surface with a laser beam. The beam is emitted by a laser device set to comply with relationship: a.V.sup.2+b.F.sup.2+c.VF+d.V+e.F+f<0, in which: a=10.sup.4.D+2×10.sup.6, b=0.5×10.sup.6.D−150×10.sup.6, c=0.5×10.sup.6.D−300×10.sup.6, d=5×10.sup.3.D−2.5×10.sup.6, e=−5×10.sup.3.D+2.0×10.sup.6, and f=−5×10.sup.9.D+1.8×10.sup.12. V is expressed in mm/second, D is expressed in mm and F is expressed in kHz.