A cubic boron nitride sintered material includes 40% by volume or more and 96% by volume or less of cubic boron nitride grains and 4% by volume or more and 60% by volume or less of a binder phase, and the cubic boron nitride grains have a dislocation density of less than 1×10.sup.5/m.sup.2.

A cubic boron nitride sintered material includes 40% by volume or more and 96% by volume or less of cubic boron nitride grains and 4% by volume or more and 60% by volume or less of a binder phase, and the cubic boron nitride grains have a dislocation density of less than 1×10.sup.5/m.sup.2.

CERMET fuel element includes a fuel meat of consolidated ceramic fuel particles (preferably refractory-metal coated HALEU fuel kernels) and an array of axially-oriented coolant flow channels. Formation and lateral positions of coolant flow channels in the fuel meat are controlled during manufacturing by spacer structures that include ceramic fuel particles. In one embodiment, a coating on a sacrificial rod (the rod being subsequently removed) forms the coolant channel and the spacer structures are affixed to the coating; in a second embodiment, a metal tube forms the coolant channel and the spacer structures are affixed to the metal tube. The spacer structures laterally position the coolant channels in spaced-apart relation and are consolidated with the ceramic fuel particles to form CERMET fuel meat of a fuel element, which are subsequently incorporated into fuel assemblies that are distributively arranged in a moderator block within a nuclear fission reactor, in particular for propulsion.

A metal-ceramic article and method for creating the same is disclosed in which the article has undergone machining to remove outer surface volume. The article is then treated to enhance the characteristics of at least the machined surface to be comparable to the original surface. In the disclosed application the machining extends into an inner layer of the article in which the article consists purely of a metal.

A metal-ceramic article and method for creating the same is disclosed in which the article has undergone machining to remove outer surface volume. The article is then treated to enhance the characteristics of at least the machined surface to be comparable to the original surface. In the disclosed application the machining extends into an inner layer of the article in which the article consists purely of a metal.

A three-dimensional shaped article production method according to the invention is a method for producing a three-dimensional shaped article by stacking layers formed in a predetermined pattern, wherein a series of steps including a composition supply step of supplying a composition containing a plurality of particles to a predetermined part, and a bonding step of bonding the particles by irradiation with a laser light is performed repeatedly, and the composition supply step includes a step of forming a first region using a first composition containing first particles as the composition, and a step of forming a second region using a second composition containing second particles which are different from the first particles as the composition, and the bonding of the particles in the first region and the bonding of the particles in the second region are performed by irradiation with laser lights with a different spectrum.

A three-dimensional shaped article production method according to the invention is a method for producing a three-dimensional shaped article by stacking layers formed in a predetermined pattern, wherein a series of steps including a composition supply step of supplying a composition containing a plurality of particles to a predetermined part, and a bonding step of bonding the particles by irradiation with a laser light is performed repeatedly, and the composition supply step includes a step of forming a first region using a first composition containing first particles as the composition, and a step of forming a second region using a second composition containing second particles which are different from the first particles as the composition, and the bonding of the particles in the first region and the bonding of the particles in the second region are performed by irradiation with laser lights with a different spectrum.

A method of producing a cubic boron nitride sintered material includes: forming an organic cubic boron nitride powder by attaching an organic substance onto a cubic boron nitride source material powder; preparing a powder mixture including more than or equal to 85 volume % and less than 100 volume % of the organic cubic boron nitride powder and a remainder of a binder source material powder by mixing the organic cubic boron nitride powder and the binder source material powder, the binder source material powder including WC, Co and Al; and obtaining the cubic boron nitride sintered material by sintering the powder mixture.

A method of producing a cubic boron nitride sintered material includes: forming an organic cubic boron nitride powder by attaching an organic substance onto a cubic boron nitride source material powder; preparing a powder mixture including more than or equal to 85 volume % and less than 100 volume % of the organic cubic boron nitride powder and a remainder of a binder source material powder by mixing the organic cubic boron nitride powder and the binder source material powder, the binder source material powder including WC, Co and Al; and obtaining the cubic boron nitride sintered material by sintering the powder mixture.

A method of producing a cubic boron nitride sintered material includes: forming an organic cubic boron nitride powder by attaching an organic substance onto a cubic boron nitride source material powder; preparing a powder mixture including more than or equal to 85 volume % and less than 100 volume % of the organic cubic boron nitride powder and a remainder of a binder source material powder by mixing the organic cubic boron nitride powder and the binder source material powder, the binder source material powder including WC, Co and Al; and obtaining the cubic boron nitride sintered material by sintering the powder mixture.