Abstract: A composition is provided that includes a plurality of calcined particles of terbium aluminum oxide having a mean particle domain size of between 30 and 600 nanometers. A translucent article having a surface includes polycrystalline terbium aluminum garnet having a mean grain size from 1 to 10 microns and light scattering inclusions of aluminum-rich oxide and/or terbium-rich oxide that are present at less than 2 surface area percent of the surface. A process for forming such an article involves sintering the above provided composition at a temperature between 1500° C. and 1700° C. to yield a sintered article. The article has improved translucency and even transparency as sintering is performed under vacuum at a temperature between 1610° C. and 1680° C. Hot isostatic pressing alone or in combination with article polishing also improves article translucency.

Abstract: The present invention aims to provide a sintered body and a component used in a plasma processing apparatus. The sintered body and the component are mainly composed of a cerium oxide, which is excellent in corrosion resistance to halogen-based gas or plasma, and can reduce resistance. The cerium oxide can also suppress contamination of metal due to impurity caused by the constituent material of the ceramic even in a halogen plasma process, so that it can preferably be used, as a substitute of an yttria, for a component in a plasma processing apparatus for manufacturing a semiconductor or liquid crystal. A sintered body is used, wherein at least the portion exposed to plasma is formed by adding an yttria with a purity of 99% or more in an amount of 3 parts by weight or more and 100 parts by weight or less to 100 parts by weight of a cerium oxide having purity of 99% or more. Alternatively, a component covered by a sprayed film having the composition same as described above is used.

Abstract: Disclosed are a gradient bioceramic coating comprising a rare earth oxide, a broadband laser method for preparing the bioceramic coating, and the use of the bioceramic coating in the field of medical materials.

Abstract: An oxygen excess type metal oxide expressed with the following formula (1) and exhibiting high speed reversible oxygen diffusibility whereby a large amount of excess oxygen is diffused at a high speed and reversibly in a low temperature region: AjBkCmDnO7+???(1) where A: one or more trivalent rare earth ions and Ca B: one or more alkaline earth metals C, D: one or more oxygen tetra-coordinated cations among which at least one is a transition metal, where j>0, k>0, and, independently, m?0, n?0, and j+k+m+n=6, and 0<??1.5.

Abstract: Compositions suitable for use as cores and shell molds for casting of reactive metal alloys, and casting processes for producing components from such alloys. The composition contains a sintered particulate material of hafnia and at least one additional metal oxide in amounts to yield a ceramic composition containing up to 70 molar percent of hafnia, wherein the additional metal oxide is a rare-earth oxide, the sintered particulate material contains first and second phases, the first phase is the rare-earth oxide and hafnia in solid solution, the second phase is a compound of the rare-earth oxide and hafnia, and the second phase is less reactive with the reactive metal alloy than the first phase.

Abstract: Lasing systems utilizing YAG and methods for producing a YAG suitable for lasing are provided. The lasing system comprises a laser activator and a laser host material is provided. The laser host material comprises a transparent polycrystalline yttrium aluminum garnet material defined by a low porosity of less than about 3 ppm.

Abstract: The present invention provides a method of manufacturing an yttria (Y2O3) sintered body having high density and excellent plasma-resistance. The yttria sintered body has a structure in which a Y2O3 crystal and a Y3BO6 crystal are included as the constituent crystal thereof. In production of the yttria sintered body, a boron oxide (B2O3) of 0.02 wt % to 10 wt % is added to an yttria (Y2O3) powder, the mixed powder is formed, and thereafter sintered at 1300-1600° C.

Abstract: Abrasive particles comprising ceramic (including glasses, crystalline ceramics, and glass-ceramics) comprising (on a theoretical oxide basis) Al2O3 and at least one other metal oxide (e.g., REO and; REO and at least one of ZrO2 or HfO2) and methods of making the same. The abrasive particles can be incorporated into a variety of abrasive articles, including bonded abrasives, coated abrasives, nonwoven abrasives, and abrasive brushes.

Abstract: A sintered body for thermistor element of the invention is a sintered body for thermistor element containing Sr, Y, Mn, Al, Fe, and O, wherein not only respective liquid crystal phases of a perovskite type oxide and a garnet type oxide are contained, but also a liquid crystal phase of at least one of an Sr—Al based oxide and an Sr—Fe based oxide. FeYO3 and/or AlYO3 is selected as the foregoing perovskite type oxide, and at least one member selected from Y3Al5O12, Al2Fe3Y3O12, and Al3Fe2Y3O12 is selected as the foregoing garnet type oxide, respectively by the powder X-ray diffraction analysis.

Abstract: Ceramic materials with relatively high resistance to wetting by various liquids, such as water, are presented, along with articles made with these materials, methods for making these articles and materials, and methods for protecting articles using coatings made from these materials. One embodiment is a material comprising a primary oxide and a secondary oxide. The primary oxide comprises cerium and hafnium. The secondary oxide comprises a secondary oxide cation selected from the group consisting of the rare earth elements, yttrium, and scandium. Another embodiment is a material comprising a primary oxide and a secondary oxide. The primary oxide comprises cerium or hafnium. The secondary oxide comprises (i) praseodymium or ytterbium, and (ii) another cation selected from the group consisting of the rare earth elements, yttrium, and scandium.

Abstract: A coated plastic substrate module (100) includes a plastic substrate (110), an organic coating (130), and a modulating film (120) sandwiched therebetween. The modulating film is made from partially stabilized zirconia. A method for manufacturing a coated plastic substrate module includes the following steps: providing a plastic substrate; forming a modulating film on the plastic substrate, the modulating film being made from partially stabilized zirconia; forming an organic coating on the modulating film; and annealing the treated plastic substrate having the modulating film and organic coating.

Abstract: Components of semiconductor processing apparatus axe formed at least: partially of erosion, corrosion and/or corrosion-erosion resistant ceramic materials. Exemplary ceramic materials can include at least one oxide, nitride, boride, carbide and/or fluoride of hafnium, strontium, lanthanum oxide and/or dysprosium. The ceramic materials can be applied as coatings over substrates to form composite components, or formed into monolithic bodies. The coatings can protect substrates from physical and/or chemical attack. The ceramic materials can be used to form plasma exposed components of semiconductor processing apparatus to provide extended service lives.

Abstract: Components of semiconductor processing apparatus are formed at least partially of erosion, corrosion and/or corrosion-erosion resistant ceramic materials. Exemplary ceramic materials can include at least one oxide, nitride, boride, carbide and/or fluoride of hafnium, strontium, lanthanum oxide and/or dysprosium. The ceramic materials can be applied as coatings over substrates to form composite components, or formed into monolithic bodies. The coatings ca protect substrates from physical and/or chemical attack. The ceramic materials can be used to form plasma exposed components of semiconductor processing apparatus to provide extended service lives.

Abstract: The present invention provides a cubic boron nitride sintered body, which achieves both of superior chipping resistance and wear resistance. In accordance with a first aspect of the present invention, a cubic boron nitride (cBN) sintered body contains cubic boron nitride particles and a bonding material used for bonding the cBN particles to one another. This sintered body is constituted by cBN particles in a range from 70 vol % to 98 vol % and a residual bonding material made from a Co compound, an Al compound and WC and a solid solution of these. Moreover, the cBN particles in the sintered body contain 0.03 wt % or less of Mg and 0.001 wt % or more to 0.05 wt % or less of Li. In accordance with a second aspect of the present invention, the cubic boron nitride sintered body has a composition in which the bonding material of the first aspect is changed to an Al compound.

Abstract: The invention relates to a light emitting device, especially a LED comprising a ceramic garnet material.

Abstract: Conventional glass compositions including bismuth as a fluorescent element have a broad amplification wavelength region but do not allow the emission intensity in the 1.3-?m range to be sufficiently high through the excitation caused by light in the 0.8-?m and 0.98-?m ranges. The present invention provides a glass composition including: bismuth; a glass network former; and at least one element selected from the group consisting of dysprosium, erbium, ytterbium, neodymium, thulium, holmium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and molybdenum (except for tetravalent titanium and trivalent iron), wherein the glass composition emits fluorescence in an infrared wavelength region, with the bismuth functioning as a fluorescent source through irradiation of excitation light. The emission intensity is increased by the sensitization effect of the at least one element.

Abstract: A vitreous antimicrobial agent that can exhibit excellent antimicrobial properties when added to various types of resins, that has excellent discoloration resistance and hot water resistance, and that can easily be produced at a commercial scale. The vitreous antimicrobial agent includes, relative to 100 mass % of total glass components, 0.1 to 2 mass % of Ag2O, 40.5 to 49 mass % of ZnO, 6 to 9.5 mass % of SiO2, 30.5 to 39.5 mass % of B2O3, 2 to 10 mass % of an alkaline earth metal oxide, and 6 to 7.5 mass % of Na2O; the vitreous antimicrobial agent comprising, in addition to these, 0.01 to 5 mass % of CeO2 as necessary. An antimicrobial resin composition and an antimicrobial product including the vitreous antimicrobial agent.

Abstract: A corrosion-resistant silicon nitride ceramics in which an adhesion enhancing layer (3), a stress relaxing layer (4) and a crack extension preventing layer (5) are laminated in this order on a ceramic substrate (2) composed mainly of silicon nitride, and a surface corrosion-resistant layer (6) composed mainly of zirconium oxide stabilized by an element of the group 3a of the periodic table is laminated. The thermal expansion coefficient (?0) of the ceramic substrate (2), the thermal expansion coefficient(?1) of the adhesion enhancing layer (3), and the thermal expansion coefficient (?2) of the stress relaxing layer (4), the thermal expansion coefficient (?3) of the crack extension preventing layer (5), and the thermal expansion coefficient (?4) of the surface corrosion-resistant layer (6) satisfy the following relational expressions (I) to (III): ?0??1??(I) ?3<?2??(II) ?3<?4??(III).

Abstract: An embodiment of the present invention provides a method of making an electronically tunable dielectric material comprising mixing particles of at least one electronically tunable dielectric phase and particles of at least one compound of low loss complex perovskites, and particles of optional one other family of materials; and sintering the material.

Abstract: Provided is a translucent ceramic which has a high Abbe number, is advantageous in aberration correction, and can be easily produced. The translucent ceramic contains, as a main component, a garnet type compound represented by the General Formula: Y3AlvOw, wherein the condition of 4.4?v?5.4 is satisfied and w is a positive number for maintaining electrical neutrality, in which the Al is partially or entirely substituted by Ga and the Y is optionally partly substituted by Gd. The translucent ceramic is suitably used, for example, for lenses arranged with a diaphragm interposed therebetween in a Gauss lens optical system, such as an optical system for single-lens reflex cameras.

Abstract: Abrasive particles and methods of making the same. Embodiments of the invention can be used to make abrasive particles. The abrasive particles can be incorporated into a variety of abrasive articles, including bonded abrasives, coated abrasives, nonwoven abrasives, and abrasive brushes.

Abstract: A dielectric ceramic composition including dielectric particles comprising a main ingredient phase having barium titanate as its main ingredient and a diffusion phase present at the periphery of said main ingredient phase, wherein when an average value of the depth where sub ingredient elements present at said diffusion phase diffuses from a surface of said diffusion phase toward a center of said dielectric particle is designated as an average diffusion depth, a dispersion of the average diffusion depth among the dielectric particles is, in terms of CV value, 5 to 30%. According to the present invention, an electronic device excellent in all of the dielectric constant, high temperature accelerated life, TC bias, and IR temperature dependency can be provided.

Abstract: A rare earth-based core for use in the casting of a reactive metal is described. The core contains a ceramic composition which includes at least about 10% by weight of monoclinic rare earth aluminate (RE4Al2O9), wherein RE represents at least one rare earth element; and at least about 10% by weight of at least one free rare earth oxide. The ceramic phase of the composition may include a microstructure which comprises a multitude of substantially spherical pores which are formed as a result of the removal of aluminum metal from the core composition during a heat treatment step. Additional embodiments relate to a method for the fabrication of a ceramic core, employing a rare earth oxide, aluminum metal, and a binder. Methods for removing cores from a cast part are also described.

Abstract: Specialty ceramic materials which resist corrosion/erosion under semiconductor processing conditions which employ a corrosive/erosive plasma. The corrosive plasma may be a halogen-containing plasma. The specialty ceramic materials have been modified to provide a controlled electrical resistivity which suppresses plasma arcing potential.

Abstract: A rare-earth oxide sintered body, or corrosion-resistant material, having low sintering temperature and high density is prepared by adding a boron compound at a ratio of 0.06 mol % or more and less than 25 mol % when converted into boron oxide (B2O3) to oxide powder of at least one of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and Sc, after which the mixed powder is formed and sintered. The sintered body comprises at least one of La2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3, and Sc2O3, and at least one of Ln3BO6 (Ln=La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, and Lu), and Sc3BO6 as a main constituent crystal thereof.

Abstract: A nonlinear resistor ceramic composition has a major component containing zinc oxide, a first minor component containing an oxide of a rare-earth metal, a second minor component containing an oxide of Ca, and a third minor component containing an oxide of Si. A percentage of the second minor component to 100 moles of the major component is in the range of 2 atomic % ? the second minor component <80 atomic % in terms of Ca. A percentage of the third minor component to 100 moles of the major component is in the range of 1 atomic % ? the third minor component <40 atomic % in terms of Si. An atomic ratio of Ca to Si (Ca/Si) is not less than 1.

Abstract: To provide a yttria sintered body having an excellent corrosion resistance to halogen-based corrosive gases and plasma and an excellent thermal shock resistance, and adapted for use as a component member in manufacturing apparatuses for semiconductor and liquid crystal devices, particularly in a plasma process apparatus. A yttria sintered body including tungsten of an average particle size of 3 ?m or less dispersed in the yttria so that a ratio of the tungsten relative to the yttria is ranging from 1 to 50% in terms of weight, and having an open pore rate of 0.2% or less and a thermal shock resistance by water submersion method of 200° C. or larger.

Abstract: A composition is provided that includes a plurality of calcined particles of terbium aluminum oxide having a mean particle domain size of between 30 and 600 nanometers. A translucent article having a surface includes polycrystalline terbium aluminum garnet having a mean grain size from 1 to 10 microns and light scattering inclusions of aluminum-rich oxide and/or terbium-rich oxide that are present at less than 2 surface area percent of the surface. A process for forming such an article involves sintering the above provided composition at a temperature between 1500° C. and 1700° C. to yield a sintered article. The article has improved translucency and even transparency as sintering is performed under vacuum at a temperature between 1610° C. and 1680° C. Hot isostatic pressing alone or in combination with article polishing also improves article translucency.

Abstract: Circuit modules and methods of construction thereof that contain composite meta-material dielectric bodies that have high effective values of real permittivity but which minimize reflective losses, through the use of host dielectric (organic or ceramic), materials having relative permittivities substantially less than ceramic dielectric inclusions embedded therein. The composite meta-material bodies permit reductions in physical lengths of electrically conducting elements such as antenna element(s) without adversely impacting radiation efficiency. The meta-material structure may additionally provide frequency band filtering functions that would normally be provided by other components typically found in an RF front-end.

Abstract: A method of forming (and an apparatus for forming) a metal-doped aluminum oxide layer on a substrate, particularly a semiconductor substrate or substrate assembly, using a vapor deposition process.

Abstract: Aqueous dispersion containing: at least one metal oxide selected from the group consisting of alpha-aluminium oxide, cerium oxide, silicon dioxide, titanium dioxide and zirconium dioxide and in addition at least one transition aluminium oxide which is present in the form of aggregates of primary particles, wherein the total content of metal oxide and transition aluminium oxide is from 60 to 75% by weight, based on the total amount of the dispersion, the content of transition aluminium oxide is from 30 to 45% by weight, based on the total amount of the dispersion, the BET surface area of the transition aluminium oxide is from 30 to 90 m2/g, the mean aggregate diameter of the transition aluminium oxide is less than 100 nm, the mean particle diameter of the metal oxide is from 100 to 500 nm, and a dispersant selected from the group consisting of polyaluminium hydroxychloride, polyaluminium hydroxynitrate and/or polyaluminium hydroxysulphate.

Abstract: A polycrystalline body comprising aluminum oxide, magnesium oxide, hafnium oxide, and yttrium oxide in which alumina grains have an average size of at least 10 ?m and wherein the yttrium oxide is present in an amount of at least 6 ppm of the weight of the ceramic body, and the magnesium and hafnium oxides are present at a molar ratio of about 0.5:1 to about 3:1.

Abstract: A yttria sintered body contains an amount of silicon carbide within a range of 5 to 40% by volume, has a volume resistivity at room temperature within a range of 1×101 to 1×1017 ?·cm, and is adapted for application to an electrostatic chuck.

Abstract: It is an object of the present invention to provide a ceramic member with excellent balance between oxygen ion conductivity and endurance (resistance to cracking and the like), an oxygen ion permeation module and a chemical reactor such as an oxygen separator, using such a ceramic member. The ceramic member with oxygen ion conductivity in accordance with the present invention has a perovskite-type crystal structure and a composition represented by the general formula: (Ln1?xMx)(Ti1?yFey)O3 (where Ln represents at least one element selected from lanthanoids, and M represents at least one element selected from the group containing Sr, Ca, and Ba, 0<x<1, 0.4?y<1, x+y?1). The oxygen ion permeation module composed by employing such a ceramic member can be used as a structural component of an oxygen separator, an oxidation reactor (for example, a reactor for partial oxidation of hydrocarbons), and the like.

Abstract: A method of fabricating doped quartz component is provided herein. In one embodiment, the doped quartz component is a yttrium doped quartz ring configured to support a substrate. In another embodiment, the doped quartz component is a yttrium and aluminum doped cover ring. In yet another embodiment, the doped quartz component is a yttrium, aluminum and nitrogen containing cover ring.

Abstract: The object of the present invention is to provide a rare-earth oxide sintered body having low sintering temperature and high density. A boron compound is added at a ratio of 0.06 mol % or more and less than 25 mol % when converted into boron oxide (B2O3) to oxide powder of at least one of La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and Sc, the mixed powder is formed and sintered.

Abstract: As for the voltage non-linear resistance element layer 2, a sintered body having ZnO as a main component is used. In this sintered body, Pr, Co, Ca, and either Cu or Ni are added. The ranges are; 0.05 to 5.0 atm % of Pr, 0.1 to 20 atm % of Co, 0.01 to 5.0 atm % of Ca, and 0.0005 to 0.05 atm % of either Cu or Ni. Within these ranges, the capacitance changing rate can be made to equal or less than 10 % at 85° C. when 25° C. is taken as standard.

Abstract: A composition is provided that includes a plurality of calcined particles of terbium aluminum oxide having a mean particle domain size of between 30 and 600 nanometers. A translucent article having a surface includes polycrystalline terbium aluminum garnet having a mean grain size from 1 to 10 microns and light scattering inclusions of aluminum-rich oxide and/or terbium-rich oxide that are present at less than 2 surface area percent of the surface. A process for forming such an article involves sintering the above provided composition at a temperature between 1500° C. and 1700° C. to yield a sintered article. The article has improved translucency and even transparency as sintering is performed under vacuum at a temperature between 1610° C. and 1680° C. Hot isostatic pressing alone or in combination with article polishing also improves article translucency.

Abstract: The present invention provides a cubic boron nitride sintered body, which achieves both of superior chipping resistance and wear resistance. In accordance with a first aspect of the present invention, a cubic boron nitride (cBN) sintered body contains cubic boron nitride particles and a bonding material used for bonding the cBN particles to one another. This sintered body is constituted by cBN particles in a range from 70 vol % to 98 vol % and a residual bonding material made from a Co compound, an Al compound and WC and a solid solution of these. Moreover, the cBN particles in the sintered body contain 0.03 wt % or less of Mg and 0.001 wt % or more to 0.05 wt % or less of Li. In accordance with a second aspect of the present invention, the cubic boron nitride sintered body has a composition in which the bonding material of the first aspect is changed to an Al compound.

Abstract: A ceramic discharge vessel is provided wherein the vessel comprises a hollow body for enclosing a discharge and the hollow body is made of a polycrystalline dysprosium oxide containing a luminescent dopant that emits one or more visible light wavelengths when stimulated by radiation generated by the discharge. Preferably, the polycrystalline dysprosium oxide has been doped with one or more of europium, cerium, or terbium in an amount from about 0.1 to about 10 percent by weight on an oxide basis.

Abstract: A corrosion resistant member made of the Y2O3 sintered material that contains 99.9% by weight or more Y in terms of Y2O3, and has a difference in mean crystal grain size between the surface and the inside region of the Y2O3 sintered material not larger than 30 ?m.

Abstract: A translucent ceramic includes a perovskite-type compound as a main component having a composition represented by the general formula (La1-x(Sr1-a-bBaaCab)x)((Al1-cGac)1-y(Ta1-dNbd)y)vOw (wherein 0<x?1, 0<y?0.6, 0.4?y/x?0.6, 0?a?1, 0?b?1, 0?c?1, 0?d?1, 0.9?v?1.1 and w is a positive number for keeping an electrical neutrality). The translucent ceramic has a high refractive index and a large Abbe number. Therefore, the translucent ceramic has an advantage in correction of aberration and is preferably used for lenses, which are disposed so as to hold a diaphragm therebetween, in a Gauss lens optical system such as an optical system for a single-lens reflex camera.

Abstract: The object of the present invention is to provide an yttria (Y2O3) sintered body having high density and excellent plasma-resistance. The yttria sintered body has a structure in which a Y2O3 crystal and a Y3BO6 crystal are included as the constituent crystal thereof. In order to produce the yttria sintered body, a boron oxide (B2O3) of 0.02 wt % to 10 wt % is added to an yttria (Y2O3) powder, the mixed powder is formed, and thereafter sintered at 1300-1600° C.

Abstract: A ceramic member having a high density, small grain diameter, and excellent plasma resistance is provided. The ceramic member is constituted of a fine structure composed of fine grains, which is a ceramic member comprising an yttria as a main component and obtained through firing, wherein the ceramic member has an open porosity, as determined through a measurement by the Archimedes method, of less than 0.5%. By diminishing open voids, sites which is an origin of plasma erosion can be diminished. Thus, a ceramic member having excellent plasma resistance can be provided. By inhibiting abnormal grain growth to form a ceramic member constituted of stall grains, particle contamination by dusting can be reduced. Thus, plasma resistance and preventing particulate contamination can be improved.

Abstract: The present invention provides a fuel cell in which electricity is generated and a paraffin is converted to an olefin. Between the anode and cathode compartment of the fuel cell is a ceramic membrane of the formula BaCe0.85-eLfY0.05-0.25O(3-?) wherein L is a lanthanide and f is from 0 to 0.25 and ? is the oxygen deficiency in the ceramic.

Abstract: A novel solution route has been developed that after heat-treatment to 500-600° C. under inert atmosphere, yields highly porous composites of nano-sized metal (Ni) particle inclusions in ceramics (Al2O3). Metal loadings could be made from <1% to >95% Ni. The metal inclusion sizes in the Ni-Al2O3 system with the 10 atom % Ni sample were 4-7 nm, while for the 75 atom % Ni sample they were 5-8 nm. It was shown that the 10 atom % Ni sample could be used as a catalyst for the conversion of CO2 and CH4 in the temperature range 550-700° C., while higher temperatures led to growth of the Ni particles and carbon poisoning over time. The solution routes could also be deposited as thin dense films containing <10 nm Ni particles. Such films with high Ni-particle loadings deposited on aluminium substrates have shown very good solar heat absorber proficiency and provide good substrates for carbon tube growth.

Abstract: The present invention relates to cerium oxide powder and a process for producing the same. The cerium oxide powder of the invention, which is produced by mixing a cerium source such as cerium oxide, cerium hydroxide and cerium carbonate with an alkali metal compound, as flux, and performing high temperature treatment, may have a variety particle size while having spherical shape.

Abstract: Aluminum titanate precursor batch compositions comprising a recycled aluminum titanate component, at least a portion of the recycled aluminum titanate component being comprised of a recycled pre-reacted aluminum titanate composition or alternatively of an un-reacted green aluminum titanate precursor composition, and methods for producing aluminum titanate ceramic articles utilizing the inventive batch compositions.

Abstract: A transparent sintered yttrium aluminum garnet ceramic material formed from a solid-state reaction of a mixture of yttrium oxide powder and aluminum oxide powder during sintering. The ceramic material preferably has an in-line transmission of greater than 75% so it may used to fabricate arc tubes for high intensity discharge lamps used in automotive headlamps.

Abstract: A yttria sintered body is provided which includes yttria as a principal ingredient and 5 to 40 vol. % silicon nitride, and which exhibits enhanced corrosion resistance and mechanical strength.