A hard material which, when used as a material of a sintered material, makes it possible to obtain a sintered material with excellent abrasion resistance, a sintered material, a cutting tool including the sintered material, a method for manufacturing the hard material and a method for manufacturing the sintered material are provided. The hard material contains aluminum, nitrogen, and at least one element selected from the group consisting of titanium, chromium, and silicon, and has a cubic rock salt structure.

A silicon nitride substrate includes silicon nitride and magnesium, in which when a surface of the silicon nitride substrate is analyzed with an X-ray fluorescence spectrometer under the specific Condition I, XB/XA is 0.8 or more and 1.0 or less.

Methods and systems for manufacturing a ceramic or glass material component supersaturated in nitrogen are disclosed. The method for manufacturing a component typically comprises receiving the ceramic or glass material within a containment vessel; simultaneously heating and applying isostatic pressure to the ceramic or glass material within the containment vessel to a first temperature and a first pressure using pressurizing nitrogen gas; holding the first temperature and the first pressure for a period of time; cooling the ceramic or glass material within the containment vessel to a second temperature while maintaining the first pressure; and depressurizing the containment vessel to a second pressure.

The invention relates to an axial turbine with a rotating casing and stationary shaft, sections for the assembly thereof, and materials for the manufacture thereof.

Provided is a method for continuously producing a silicon nitride sintered compact for enabling a continuous production of silicon nitride sintered compacts by sintering using a silicon nitride powder having a high β-phase rate. A fired compact 1 housed in a firing jig 2 contains a silicon nitride powder having at least 80% of β-transition rate and 7 to 20 m.sup.2/g of specific surface area together with a sintering additive, where the total content of aluminum element is adjusted not to exceed 800 ppm. The firing jig 2 is supplied into a continuous firing furnace equipped with a closed-type firing container 5 having at its end portions a supplying openable door 3 and a discharging openable door 4 for supplying and discharging the firing jig, a heating mechanism 6 provided on the body periphery of the firing container 5, a conveyance mechanism for supplying/discharging the firing jig into/from the firing container, and a gas-supplying mechanism for supplying an inert gas into the firing container, so that the silicon nitride is heated to a temperature in the range of 1200 to 1800° C. in an inert gas atmosphere and at a pressure of not less than 0 MPa.Math.G and less than 0.1 MPa.Math.G so as to be sintered.

A method is disclosed for forming a blended phosphor composition. The method includes the steps of firing precursor compositions that include europium and nitrides of at least calcium, strontium and aluminum, in a refractory metal crucible and in the presence of a gas that precludes the formation of nitride compositions between the nitride starting materials and the refractory metal that forms the crucible. The resulting compositions can include phosphors that convert frequencies in the blue portion of the visible spectrum into frequencies in the red portion of the visible spectrum.

A method is disclosed for forming a blended phosphor composition. The method includes the steps of firing precursor compositions that include europium and nitrides of at least calcium, strontium and aluminum, in a refractory metal crucible and in the presence of a gas that precludes the formation of nitride compositions between the nitride starting materials and the refractory metal that forms the crucible. The resulting compositions can include phosphors that convert frequencies in the blue portion of the visible spectrum into frequencies in the red portion of the visible spectrum.

An insert may include a sintered silicon nitride including β-Si.sub.3N.sub.4 as a main component. The area up to 0.5 mm deep from a surface of the sintered silicon nitride is a first region. The first region may include an oxygen content of less than 0.8% by mass. The first region may include ReMgSi.sub.2O.sub.5N (Re is at least one of Yb and Y). A cutting tool may include a holder that extends from a first end toward a second end and includes a pocket on a side of the first end, and the insert located at the pocket.

Provided are a method for producing a ceramic composite material that has a high light emission intensity, a ceramic composite material, and a light emitting device. The method for producing a ceramic composite material, includes: preparing a green body containing a nitride fluorescent material having a composition represented by the following chemical formula (I) and aluminum oxide particles mixed with each other; and performing primary sintering the green body at a temperature in a range of 1,250° C. or more and 1,600° C. or less to provide a first sintered body:
M.sub.wLn.sup.1.sub.xA.sub.yN.sub.z  (I)
wherein in the chemical formula (I), M represents at least one element selected from the group consisting of Ce and Pr; Ln.sup.1 represents at least one element selected from the group consisting of Sc, Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; A represents at least one element selected from the group consisting of Si and B; and w, x, y, and z each satisfy 0<w≤1.0, 2.5≤x≤3.5, 5.5≤y≤6.5, and 10≤z≤12.

A ceramic contains, in mass percent: Si.sub.3N.sub.4: 20.0 to 60.0%, ZrO.sub.2: 25.0 to 70.0%, and one or more oxides selected from MgO, Y.sub.2O.sub.3, CeO.sub.2, CaO, HfO.sub.2, TiO.sub.2, Al.sub.2O.sub.3, SiO.sub.2, MoO.sub.3, CrO, CoO, ZnO, Ga.sub.2O.sub.3, Ta.sub.2O.sub.5, NiO, and V.sub.2O.sub.5: 5.0 to 15.0%. The ceramic has a coefficient of thermal expansion as high as that of silicon and an excellent mechanical strength, allows fine machining with high precision, and prevents particles from being produced.