Abstract: A switch 1 includes a ceramic cylindrical tube 3, first and second end caps 5 and 7 that cover the open end in an axial direction of the ceramic cylindrical tube 3, a movable electrode 9 which slides easily on first end cap 5 and a fixed electrode 11 attached to second end cap 7. The ceramic cylindrical tube 3 is a ceramic fired body that contains 45 to 65% by weight of alumina and 35 to 55% by weight of crystallized glass. First and second end caps 5 and 7 are attached to both ends in the axial direction of the ceramic cylindrical tube 3. A low temperature metallizing layer is formed on the ends thereof, and a plating layer is formed on top of the metallizing layer where first and second end caps 5 and 7 are brazed.

Abstract: A process for producing a ceramic member for bonding, which comprises: a first step of preparing a lower layer paste with the use of a first mixture comprising nickel, tungsten and molybdenum, applying the lower layer paste to a surface of a ceramic base which is a sintered ceramic, and drying the resultant coating layer to form a lower layer after the applying; a second step of preparing an upper layer paste with the use of a second mixture comprising one of nickel and nickel oxide and at least one of copper, copper oxide, manganese and manganese oxide, applying the upper layer paste to the lower layer, and drying the resultant coating layer to form an upper layer after the applying; and a third step of heating the lower layer and the upper layer to bake the lower layer and the upper layer.

Abstract: A glazed ceramic article is provided which comprises a glaze layer formed on an outer surface of a ceramic main body. The glaze layer is made of a glaze comprising 60 to 74% by weight of Si when calculated in terms of SiO2 and 16 to 30% by weight of Al when calculated in terms of Al2O3. Such a composition can raise the softening temperature and can prevent deterioration of the appearance due to the surface roughening caused at the time of soldering of a metallic member to the ceramic main body after glost firing and deterioration of the insulation ability due to adherence of dirt to the surface of the glaze layer. A metal and ceramic assembly having such a glazed ceramic article, and a vacuum switch having such a metal and ceramic assembly are also provided.

Abstract: A metal-ceramic composite is provided in which a solder layer and a ceramic member are held in contact with each other at an annular area extending along an entire circumference of an axial end surface of the ceramic member and having an average width W (mm), and in which the average width W and an outer diameter D (mm) of the ceramic member satisfy D≧30 and (⅙)×D≧W≧(D/30)+2.6.

Abstract: A process for producing a ceramic member for bonding, which comprises: a first step of preparing a lower layer paste with the use of a first mixture comprising nickel, tungsten and molybdenum, applying the lower layer paste to a surface of a ceramic base which is a sintered ceramic, and drying the resultant coating layer to form a lower layer after the applying; a second step of preparing an upper layer paste with the use of a second mixture comprising one of nickel and nickel oxide and at least one of copper, copper oxide, manganese and manganese oxide, applying the upper layer paste to the lower layer, and drying the resultant coating layer to form an upper layer after the applying; and a third step of heating the lower layer and the upper layer to bake the lower layer and the upper layer.

Abstract: A metal-ceramic composite (a vacuum switch unit 50) having a metal member 13 having a tubular portion 13b, and a cylindrical ceramic member 55. The metal-ceramic composite (the vacuum switch unit 50) has a structure in which an end face of the tubular portion 13b of the metal member 13 is butt joined via a joint metal layer 15 to an end face 55a of the cylindrical ceramic member 55 in an edge sealed manner. In order to provide a metal-ceramic composite having a high joint strength which is less likely to cause defects such as cuts or cracks at the joint, the joint metal layer 15 and the ceramic member 55 contact each other at an annular region of W (mm) in average width which extends circumferentially about the end face 55a of the ceramic member 55. Furthermore, W and D have respective values which satisfy D≧30 {circle around (1)}; and (1/60)×D≦W≦(D/30)+3.1 {circle around (2)} where D (mm) is an outer diameter of the ceramic member.

Abstract: A vacuum switch container, a vacuum switch, a method of producing the vacuum switch container and a method of producing the vacuum switch are provided. Ceramic granulated powers are used to fill a space of a cylindrical shape defined by an outer hard metal mold having an inner diameter of 120 mm and a center hard metal pin having an outer diameter of 108 mm. A pressure of 1000 kg/cm2 is applied in an axis direction relative to the cylindrical shape by using lower and upper cylindrical punches, from both the top and bottom of the space, to produce a green compact. Next, the green compact is fired in open air at 1600° C. to produce a cylindrical ceramic fired body. Each of the end surfaces of the ceramic fired body are then ground and the ground surface is metalized. Ni plating is applied to the metalized surface, thereby forming an electroconductive layer thereon to complete the vacuum switch container.

Abstract: A ceramic member for bonding comprises: a ceramic base which is a sintered ceramic; and a metallic layer formed on the ceramic base by metallization, wherein the metallic layer comprises 70 to 85% by weight of at least one of tungsten and molybdenum and 0.5 to 8.5% by weight of nickel.

Abstract: A metal-ceramic composite (a vacuum switch unit 50) having a metal member 13 having a tubular portion 13b, and a cylindrical ceramic member 55. The metal-ceramic composite (the vacuum switch unit 50) has a structure in which an end face of the tubular portion 13b of the metal member 13 is butt joined via a joint metal layer 15 to an end face 55a of the cylindrical ceramic member 55 in an edge sealed manner. In order to provide a metal-ceramic composite having a high joint strength which is less likely to cause defects such as cuts or cracks at the joint, the joint metal layer 15 and the ceramic member 55 contact each other at an annular region of W (mm) in average width which extends circumferentially about the end face 55a of the ceramic member 55. Furthermore, W and D have respective values which satisfy D≧30 {circle over (1)}; and (1/60)×D≦W≦(D/30)+3.1 {circle over (2)} where D (mm) is an outer diameter of the ceramic member.

Abstract: A vacuum switch container, a vacuum switch, a method of producing the vacuum switch container and a method of producing the vacuum switch are provided. Ceramic granulated powders are used to fill a space of a cylindrical shape defined by an outer hard metal mold having an inner diameter of 120 mm and a center hard metal pin having an outer diameter of 108 mm. A pressure of 1000 kg/cm2 is applied in an axial direction relative to the cylindrical shape by using lower and upper cylindrical punches, from both the top and bottom of the space, to produce a green compact. Next, the green compact is fired in open air at 1600° C. to produce a cylindrical ceramic fired body. Each of the end surfaces of the ceramic fired body are then ground and the ground surface is metalized. Ni plating is applied to the metalized surface, thereby forming an electroconductive layer thereon to complete the vacuum switch container.

Abstract: A metal-ceramic composite is provided in which a solder layer and a ceramic member are held in contact with each other at an annular area extending along an entire circumference of an axial end surface of the ceramicmeber and having an average width W (mm), and in which the average width W and an outer diameter D (mm) of the ceramic member satisfy D≧30 and (1/6)×D≧W≧(D/30)+2.6.

Abstract: A ceramic member for bonding comprises: a ceramic base which is a sintered ceramic; and a metallic layer formed on the ceramic base by metallization, wherein the metallic layer comprises 70 to 85% by weight of at least one of tungsten and molybdenum and 0.5 to 8.5% by weight of nickel.

Abstract: A glazed ceramic article is provided which comprises a glaze layer formed on an outer surface of a ceramic main body. The glaze layer is made of a glaze comprising 60 to 74% by weight of Si when calculated in terms of SiO2 and 16 to 30% by weight of Al when calculated in terms of Al2O3. Such a composition can raise the softening temperature and can prevent deterioration of the appearance due to the surface roughening caused at the time of soldering of a metallic member to the ceramic main body after glost firing and deterioration of the insulation ability due to adherence of dirt to the surface of the glaze layer. A metal and ceramic assembly having such a glazed ceramic article, and a vacuum switch having such a metal and ceramic assembly are also provided.

Abstract: A porous ceramic material for a slidable member or unit such as a valve unit of a combination faucet. The porous ceramic material comprises a ceramic sintered body which is formed with pores dispersedly located therein. The pores are defined respectively by surface layers forming part of the ceramic sintered body. Each surface layer contains silicon in a content higher than that in other part of the ceramic sintered body. The porous ceramic material is prepared, for example, first by mixing ceramic powder and hollow particles each of which contains silicon so as to obtain a mixture; then by forming the mixture into a predetermined shape to obtain a formed body; and finally by sintering the formed body at a temperature higher than a melting point of each hollow particle to thus obtain the sintered body formed with pores and containing silicon.

Abstract: A porous ceramic material for a slidable member on unit such as a valve unit of a combination faucet. The porous ceramic material comprises a ceramic sintered body which is formed with pores dispersedly located therein. The pores are defined respectively by surface layers forming part of the ceramic sintered body. Each surface layer contains silicon in a content higher than that in other part of the ceramic sintered body. The porous ceramic material is prepared, for example, first by mixing ceramic powder and hollow particles each of which contains silicon so as to obtain a mixture; then by forming the mixture into a predetermined shape to obtain a formed body; and finally by sintering the formed body at a temperature higher than a melting point of each hollow particle to thus obtain the sintered body formed with pores and containing silicon.