A honeycomb structure according to at least one embodiment of the present invention includes: a honeycomb structure portion having: an outer peripheral wall; and a partition wall arranged inside the outer peripheral wall to define a plurality of cells each extending from a first end surface of the honeycomb structure portion to a second end surface thereof to form a flow path; and a pair of electrode portions arranged on an outer peripheral surface of the outer peripheral wall of the honeycomb structure portion. The electrode portions are each a porous body in which particles of silicon carbide are bound by a binding material, the silicon carbide contains α-type silicon carbide and β-type silicon carbide, and the silicon carbide has a D50 in a volume-based cumulative particle size distribution of 25 μm or less.

A semiconductor ceramic composition which is a BaTiO.sub.3 based semiconductor ceramic composition, wherein, part of Ba is replaced by at least A (at least one alkali metal element selected from Na and K), Bi and RE (at least one element selected from rare earth elements including Y), and part of Ti is replaced by at least TM (at least one element selected from the group including of V, Nb and Ta), the relationships of 0.7≦{(the content of Bi)/(the content of A)}≦1.43, 0.017≦{(the content of Bi)+(the content of A)}≦0.25, and 0<{(the content of RE)+(the content of TM)}≦0.01 are satisfied when the total content of Ti and TM is set as 1 mol, the grain sizes have a maximum peak in a grain size distribution in a range of 1.1 μm to 4.0 μm or less, and the distribution frequency of the peak is 20% or more.

An yttrium oxide-based sintered body includes yttrium oxide as a predominant component. The sintered body includes aluminum in an amount of 0.1 mass % to 0.5 mass % inclusive as reduced to aluminum oxide, has a metal content of 1,000 ppm or less, the metal excluding yttrium and aluminum, and has a relative density of 98% or higher. By virtue of the yttrium oxide-based sintered body, a plasma resistance comparable to that of a high-purity (99.9%) yttrium oxide sintered body can be achieved. Also, since the relative density is sufficiently high, plasma resistance can be enhanced. As a result, the yttrium oxide-based sintered body can be suitably used as a large-scale member by virtue of excellent mechanical strength.

The present invention discloses a method for uniformly coating metal nanoparticles without a carbon impurity on an oxide ceramic powder surface, which includes the steps of putting grinded and mixed a metal organic material and oxide ceramic powder into a rotational reaction chamber, then bubbling oxidizing gas under a rotational and heating condition to oxidize the metal organic material into a metal oxide, and finally bubbling reducing gas to reduce the metal oxide into nanoparticles in a metallic state, so as to implement the uniform coating of the nanoparticles in the metallic state, and avoid coarsening and growing problems of nanoparticles led by a long-term coating reaction under a high temperature. The present invention has a simple method and a short preparation period, and the metal nanoparticles prepared are uniformly dispersed and have wide application prospects in multiple fields like catalytic materials and conductive ceramics.

An orthodontic bracket for coupling an archwire with a tooth. The orthodontic bracket including a ceramic injection molded (CIM) bracket body including an archwire slot that is configured to receive the archwire therein. The CIM bracket body including a polycrystalline ceramic. A coating of alumina or silicon dioxide is in continuous and direct contact with at least the surfaces of the archwire slot. The orthodontic bracket is characterized by unexpectedly high torque strength. The ceramic injection molded (CIM) bracket body may include a polycrystalline ceramic having a grain size distribution characterized by an average grain size in the range of larger than 3.4 μm to about 6 μm such that the orthodontic bracket is also characterized by unexpectedly high fracture toughness. A method of making the orthodontic bracket includes injection molding a bracket using a ceramic powder, sintering the molded bracket, and coating the ceramic injection molded bracket.

A target for sputtering which enables to attain high rate film-formation of a transparent conductive film suitable for a blue LED or a solar cell. A oxide sintered body includes an indium oxide and a cerium oxide, and one or more oxide of titanium, zirconium, hafnium, molybdenum and tungsten. The cerium content is 0.3 to 9% by atom, as an atomicity ratio of Ce/(In+Ce), and the content of cerium is equal to or lower than 9% by atom, as an atomicity ratio of Ce/(In+Ce). The oxide sintered body has an In.sub.2O.sub.3 phase of a bixbyite structure has a CeO.sub.2 phase of a fluorite-type structure finely dispersed as crystal grains having an average particle diameter of equal to or smaller than 3 μm.

Provided are a sintered ceramic and a ceramic sphere which are inhibited from suffering surface peeling due to fatigue resulting from repetitions of loading and can attain an improvement in dimensional accuracy when subjected to surface processing and which have excellent wear resistance and durability.

The present invention provides a lead-free piezoelectric material having a high piezoelectric constant and a high mechanical quality factor in a wide operating temperature range. The piezoelectric material includes a perovskite-type metal oxide represented by Formula (1):
(Ba.sub.1-xCa.sub.x).sub.a(Ti.sub.1-yZr.sub.y)O.sub.3 (1.00≦a≦1.01, 0.125≦x<0.155, and 0.041≦y≦0.074)
as a main component. The metal oxide contains Mn in a content of 0.12 parts by weight or more and 0.40 parts by weight or less based on 100 parts by weight of the metal oxide on a metal basis.

A method for manufacturing a pressure measuring cell, which has a ceramic platform and a ceramic measuring membrane, wherein the measuring membrane is joined with the platform pressure tightly by an active hard solder, or braze, wherein the method includes: providing the platform, the measuring membrane and the active hard solder, or braze, positioning the active hard solder, or braze, between the platform and the measuring membrane; melting the active hard solder, or braze, by irradiating the active hard solder, or braze, by a laser, wherein the irradiating of the active hard solder, or braze, occurs through the measuring membrane; and letting the active hard solder, or braze, solidify by cooling.

An armor component including a body having a first portion including calcium boride compounds include non-stoichiometric calcium boride (CaB.sub.x) and stoichiometric calcium boride (CaB.sub.6) and having a density of at least about 80% theoretical density. In one aspect, the first portion can include a first phase comprising silicon carbide (SiC) and a second phase comprising calcium boride (CaB.sub.6). In another aspect, the first portion can further include a third phase comprising boron carbide (B.sub.4C).