A method for producing a composite of cubic boron nitride dispersed in a SiAlON ceramic. This method involves mixing silicon nitride nanoparticles, aluminum nitride nanoparticles, silica nanoparticles, calcium oxide nanoparticles, and cubic boron nitride microparticles to produce a mixture. The cubic boron nitride may be coated with nickel. The mixture is sintered to produce the composite, and this sintering may involve spark plasma sintering and/or sintering at a relatively low temperature. The composite may comprise a mixture of Ca--SiAlON and -SiAlON ceramic reinforced by boron nitride in either or both cubic and hexagonal phases.

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.

A CaSiAlON ceramic with enhanced mechanical properties and a method employing micron-sized and submicron precursors to form the CaSiAlON ceramic. The CaSiAlON ceramic comprises not more than 42 wt % silicon, relative to the total weight of the CaSiAlON ceramic. The method employs submicron particles and also allows for substituting a portion of aluminum nitride with aluminum to form the CaSiAlON ceramic with enhanced mechanical properties.

A CaSiAlON ceramic with enhanced mechanical properties and a method employing micron-sized and submicron precursors to form the CaSiAlON ceramic. The CaSiAlON ceramic comprises not more than 42 wt % silicon, relative to the total weight of the CaSiAlON ceramic. The method employs submicron particles and also allows for substituting a portion of aluminum nitride with aluminum to form the CaSiAlON ceramic with enhanced mechanical properties.

A heater tube for molten metal immersion 1 has a cylindrical heater housing part 4 equipped with a closed end 2 and an open end 3, wherein the heater housing part 4 comprises silicon nitride, a compound comprising yttrium, and a compound comprising magnesium. The heater housing part 4 has a surface roughness Ra of an outer circumferential surface of the heater housing part 4 is between 0.5 m and 10 m, inclusive.

A method for producing a composite of cubic boron nitride dispersed in a SiAlON ceramic. This method involves mixing silicon nitride nanoparticles, aluminum nitride nanoparticles, silica nanoparticles, calcium oxide nanoparticles, and cubic boron nitride microparticles to produce a mixture. The cubic boron nitride may be coated with nickel. The mixture is sintered to produce the composite, and this sintering may involve spark plasma sintering and/or sintering at a relatively low temperature. The composite may comprise a mixture of Ca--SiAlON and -SiAlON ceramic reinforced by boron nitride in either or both cubic and hexagonal phases.

A production process for a crystal oriented ceramics includes: a first step of preparing composite particles formed of particles having magnetic anisotropy having magnetic susceptibility anisotropy and seed particles having magnetic susceptibility anisotropy less than or equal to 1/10 of the magnetic susceptibility anisotropy of the particles having magnetic anisotropy and are formed of an inorganic compound having an anisotropic shape in which a crystal axis intended to be corresponds to a minor axis or a major axis; a second step of adding raw material powder including the composite particles to a solvent to prepare a slurry a third step of preparing a green compact by disposing the slurry in a static magnetic field of >0.1 tesla and drying the slurry in a state in which crystal axes of the seed particles in a major axis direction are in one direction; and a fourth step of sintering the green compact.

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.

A CaSiAlON ceramic with enhanced mechanical properties and a method employing micron-sized and submicron precursors to form the CaSiAlON ceramic. The CaSiAlON ceramic comprises not more than 42 wt % silicon, relative to the total weight of the CaSiAlON ceramic. The method employs submicron particles and also allows for substituting a portion of aluminum nitride with aluminum to form the CaSiAlON ceramic with enhanced mechanical properties.

A CaSiAlON ceramic with enhanced mechanical properties and a method employing micron-sized and submicron precursors to form the CaSiAlON ceramic. The CaSiAlON ceramic comprises not more than 42 wt % silicon, relative to the total weight of the CaSiAlON ceramic. The method employs submicron particles and also allows for substituting a portion of aluminum nitride with aluminum to form the CaSiAlON ceramic with enhanced mechanical properties.