A cBN sintered body has 40%-85% cBN by volume and 15% to 60% binder phase by volume. and inevitable impurities. The binder phase has an Al compound including Al and at least one element selected from N, O and B, and a Zr compound including Zr and at least one element selected from C, N, O and B. The Zr compound includes ZrO, or ZrO and ZrO.sub.2. In an X-ray diffraction, where a peak intensity of a (111) plane of the ZrO is I.sub.1, a peak intensity of a (101) plane of tetragonal ZrO.sub.2 is I.sub.2t and a peak intensity of a (111) plane of cubic ZrO.sub.2 is I.sub.2c, a ratio of the intensity of I.sub.1 to total intensities of I.sub.1, I.sub.2t and I.sub.2c is 0.6-1.0, and an average grain size of the Al compound is 80 nm-300 nm.

A cBN sintered material comprising cBN particles and a binder phase, in which the binder phase contains AlN and AlB.sub.2, a content proportion of cBN particles is 70 to 97 vol %, cBN sintered material has a volume resistivity up to 5×10.sup.−3 Ωcm, a rate of a peak intensity derived from Al with respect to a peak intensity derived from cBN particles is less than 1.0%, cBN particles include fine particles and coarse particles, coarse particles optionally include ultra-coarse particles, with respect to the entire cBN particles, a content proportion α of fine particles is from 10 vol %, a content proportion β of coarse particles is from 30 vol %, a content proportion γ of ultra-coarse particles is 25 vol % or less, and a total of the content proportion α of fine particles and the content proportion β of coarse particles is 50 to 100 vol %.

Disclosed herein is a ceramic matrix composite comprising a preform comprising a plurality of plies; a ceramic matrix encompassing the plies and distributed through the plies; and thermally conducting particles distributed through the ceramic matrix. Disclosed herein is a method comprising distributing thermally conducting particles between plies in a preform; infiltrating chemical vapors of a ceramic precursor into the plies; and reacting the ceramic precursor to form a matrix.

A cubic boron nitride-based sintered material includes cubic boron nitride particles of 70 to 95 vol %, in which in a structure of a cross-section of the sintered material, a binder phase with a width of 1 nm to 30 nm is present between the adjacent cubic boron nitride particles, the binder phase being made of a compound containing at least Al, B, and N and having a ratio of an oxygen content to an Al content of 0.1 or less in terms of atomic ratio.

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 cBN sinter comprising cubic boron nitride grains and a binder phase, the binder phase comprising Ti.sub.2CN and TiAl.sub.3, wherein the ratio I.sub.Ti2CN/I.sub.TiAl3 of the peak intensity I.sub.Ti2CN of Ti.sub.2CN appearing at 2θ=41.9° to 42.2° to the peak intensity I.sub.TiAl3 of TiAl.sub.3 appearing at 2θ=39.0° to 39.3° is in a range of 2.0 to 30.0 in an XRD measurement.

A silicon-containing oxide-coated aluminum nitride particle including an aluminum nitride particle and a silicon-containing oxide coating covering the surface of the aluminum nitride particle. The content of carbon atoms is less than 1000 ppm by mass, and an Si/Al atom ratio of the surface as measured by AES analysis is 0.29 or more and 5.0 or less. In another aspect, the coverage of the silicon-containing oxide coating covering the surface of the aluminum nitride particle as measured by LEIS analysis is 15% or more and 100% or less.

A ceramic material includes of β-sialon (Si.sub.(6-z)Al.sub.zO.sub.zN.sub.(8-z)), polytype 15R, an intergranular phase, and yttrium. The polytype 15R includes twin grains.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

The present invention provides a welding tool member for friction stir welding comprising a silicon nitride sintered body, wherein the silicon nitride sintered body includes an additive component other than silicon nitride in a content of 15% by mass or less, and the additive component includes three or more elements selected from Y, Al, Mg, Si, Ti, Hf, Mo and C. It is preferable that the content of the additive component is 3% by mass or more and 12.5% by mass or less. It is also preferable that the additive component includes four or more elements selected from Y, Al, Mg, Si, Ti, Hf, Mo and C. Due to above structure, there can be provided a welding tool member for friction stir welding having a high durability.