The present invention relates to a process for sintering a compacted powder of at least one oxide of a metal selected from an actinide and a lanthanide, this process comprising the following successive steps, carried out in a furnace and under an atmosphere comprising an inert gas, dihydrogen and water: (a) a temperature increase from an initial temperature T.sub.I up to a hold temperature T.sub.P, (b) maintaining the temperature at the hold temperature T.sub.P, and (c) a temperature decrease from the hold temperature T.sub.P down to a final temperature T.sub.F, in which the P(H.sub.2)/P(H.sub.2O) ratio is such that: 500<P(H.sub.2)/P(H.sub.2O)≦50 000, during step (a), from T.sub.I until a first intermediate temperature T.sub.i1 between 1000° C. and T.sub.P is reached, and P(H.sub.2)/P(H.sub.2O)≦500, at least during step (c), from a second intermediate temperature T.sub.i2 between T.sub.P and 1000° C., until T.sub.F is reached.

A dielectric ceramic composition and a multilayer ceramic capacitor comprising the same are provided. The dielectric ceramic composition includes a BaTiO.sub.3-based base material main ingredient and an accessory ingredient, where the accessory ingredient includes dysprosium (Dy) and cerium (Ce) as first accessory ingredients. A total content of Dy and Ce is greater than 0.25 mol % and equal to or less than 1.0 mol % based on 100 mol % of the base material main ingredient.

Methods for improving the wear performance of silicon nitride and/or other ceramic materials, particularly to make them more suitable for use in manufacturing biomedical implants.

A multilayer coil component including a magnetic part formed of a ferrite material, a non-magnetic part formed of a non-magnetic ferrite material, and a coiled conductive part embedded in the magnetic part and the non-magnetic part. The non-magnetic part has an Fe content of 36.0 to 48.5 mol % in terms of Fe.sub.2O.sub.3, a Zn content of 46.0 to 57.5 mol % in terms of ZnO, a V content of 0.5 to 5.0 mol % in terms of V.sub.2O.sub.5, a Mn content of 0 to 7.5 mol % in terms of Mn.sub.2O.sub.3, and a Cu content of 0 to 5.0 mol % in terms of CuO with respect to the sum of the Fe content in terms of Fe.sub.2O.sub.3, the Zn content in terms of ZnO, the V content in terms of V.sub.2O.sub.5, and if present, the Cu content in terms of CuO, and the Mn content in terms of Mn.sub.2O.sub.3.

Provided is a dielectric composition exhibiting a high strength and a high specific dielectric constant. The dielectric composition contains composite oxide particles having a composition formula represented by (Sr.sub.xBa.sub.1-x).sub.yNb.sub.2O.sub.5+y and an Al-based segregation phase. The Al segregation phase has niobium, aluminum, and oxygen.

One aspect relates to a process for producing a sintered workpiece, which includes sintering of a ceramic material at a temperature of at least 1000° C. and in an atmosphere, in the case of which the partial pressure of atmospheric air is reduced to less than 10.sup.−6-times, based on the ambient air at the same temperature under equilibrium conditions.

In order to provide a dielectric composition having high density even when fired at a relatively low temperature, the main component of a dielectric composition includes tantalum and at least one of barium or strontium, and the subcomponent of the dielectric composition includes at least one element selected from the group consisting of vanadium, titanium, and aluminum.

A dielectric ceramic composition contains dielectric particles containing a main component represented by a composition formula (Ba.sub.1-x-ySr.sub.xCa.sub.y).sub.m(Ti.sub.1-zZr.sub.z)O.sub.3 and grain boundaries present between the dielectric particles. The values of m, x, y, and z in the composition formula are all molar ratios. In the composition formula, 0.9≤m≤1.4, 0≤x<1.0, 0<y≤1.0, 0.9≤(x+y)≤1.0, and 0.9≤z≤1.0 are satisfied. The dielectric particles contain specific structural particles having a predetermined intragranular structure, and each of the specific structural particles intragranularly includes a first region and a second region having different Ca concentrations from each other. C2/C1 is less than 0.8 in which C1 is an average value of the Ca concentration in the first region and C2 is an average value of the Ca concentration in the second region.

A ceramic matrix composite manufacturing method includes: forming a zirconia-sol containing layer that contains zirconia sol, on fabric having an interface layer formed on a periphery of each of a plurality of ceramic-made fibers; impregnating the fabric having the zirconia-sol containing layer formed, with a polymer as a precursor, to form a body; supplying oxygen to the polymer included in the body; heating the body in an inert gas atmosphere to cause a reaction of the polymer to form a matrix; and heating the body in an oxygen atmosphere to remove the interface layer, after supplying the oxygen and heating the body in the inert gas atmosphere, to generate a ceramic matrix composite in which the matrix is interposed between the fibers.

An oxide superconductor of an embodiment includes an oxide superconductor layer having a continuous Perovskite structure containing rare earth elements, barium (Ba), and copper (Cu). The rare earth elements contain a first element which is praseodymium (Pr), at least one second element selected from the group consisting of neodymium (Nd), samarium (Sm), europium (Eu), and gadolinium (Gd), at least one third element selected from the group consisting of yttrium (Y), terbium (Tb), dysprosium (Dy), and holmium (Ho), and at least one fourth element selected from the group consisting of erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).