A method for producing microencapsulated fuel pebble fuel more rapidly and with a matrix that engenders added safety attributes. The method includes coating fuel particles with ceramic powder; placing the coated fuel particles in a first die; applying a first current and a first pressure to the first die so as to form a fuel pebble by direct current sintering. The method may further include removing the fuel pebble from the first die and placing the fuel pebble within a bed of non-fueled matrix ceramic in a second die; and applying a second current and a second pressure to the second die so as to form a composite fuel pebble.

A method for producing microencapsulated fuel pebble fuel more rapidly and with a matrix that engenders added safety attributes. The method includes coating fuel particles with ceramic powder; placing the coated fuel particles in a first die; applying a first current and a first pressure to the first die so as to form a fuel pebble by direct current sintering. The method may further include removing the fuel pebble from the first die and placing the fuel pebble within a bed of non-fueled matrix ceramic in a second die; and applying a second current and a second pressure to the second die so as to form a composite fuel pebble.

According to the present invention, a dense composite material includes titanium silicide in an amount of 43 to 63 mass %; silicon carbide in an amount less than the mass percentage of the titanium silicide; and titanium carbide in an amount less than the mass percentage of the titanium silicide. In the dense composite material, a maximum value of interparticle distances of the silicon carbide is 40 μm or less, a standard deviation of the interparticle distances is 10 or less, and an open porosity of the dense composite material is 1% or less.

According to the present invention, a dense composite material includes titanium silicide in an amount of 43 to 63 mass %; silicon carbide in an amount less than the mass percentage of the titanium silicide; and titanium carbide in an amount less than the mass percentage of the titanium silicide. In the dense composite material, a maximum value of interparticle distances of the silicon carbide is 40 μm or less, a standard deviation of the interparticle distances is 10 or less, and an open porosity of the dense composite material is 1% or less.

A silicon carbide flow reactor fluidic module comprises a monolithic closed-porosity silicon carbide body, a tortuous fluid passage extending through the silicon carbide body, the tortuous fluid passage having an interior surface, and one or more thermal control fluid passages also extending through the silicon carbide body, the interior surface having a surface roughness of less than 10 μm Ra. A process for forming such modules is also disclosed.

A silicon carbide flow reactor fluidic module comprises a monolithic closed-porosity silicon carbide body, a tortuous fluid passage extending through the silicon carbide body, the tortuous fluid passage having an interior surface, and one or more thermal control fluid passages also extending through the silicon carbide body, the interior surface having a surface roughness of less than 10 μm Ra. A process for forming such modules is also disclosed.

A ceramic substrate made of a dielectric material including silicon carbide particles, which is used as a forming material, in which the number of the silicon carbide particles per unit area on the surface of the substrate is smaller than the number of the silicon carbide particles per unit area in a cross section of the substrate.

A module and a process for forming a monolithic substantially closed-porosity silicon carbide fluidic module having a tortuous fluid passage extending through the module, the tortuous fluid passage having an interior surface, the interior surface having a surface roughness in the range of from 0.1 to 10 μm Ra. The process includes positioning a positive fluid passage mold within a volume of silicon carbide powder, the powder coated with a binder; pressing the volume of silicon carbide powder with the mold inside to form a pressed body; heating the pressed body to remove the mold; and sintering the pressed body.

Among two main surfaces of a heat dissipation member, one main surface is curved to be convex in an outward direction and the other convex in an inward direction. When a straight line passing through both endpoints P.sub.1 and P.sub.2 of the curve is l.sub.1, a point at which a distance to l.sub.1 on the curve is maximum is P.sub.max, an intersection point between l.sub.1 and a perpendicular drawn from P.sub.max to l.sub.1 is P.sub.3, a middle point of a line segment P.sub.1P.sub.3 is P.sub.4, an intersection point between the curve and a straight line that passes through P.sub.4 and is perpendicular to l.sub.1 is P.sub.mid, a length of the line segment P.sub.1P.sub.3 is L, a length of a line segment P.sub.3P.sub.max is H, and a length of a line segment P.sub.4P.sub.max is h, (2 h/L)/(H/L) is 1.1 or more.

Among two main surfaces of a heat dissipation member, one main surface is curved to be convex in an outward direction and the other convex in an inward direction. When a straight line passing through both endpoints P.sub.1 and P.sub.2 of the curve is l.sub.1, a point at which a distance to l.sub.1 on the curve is maximum is P.sub.max, an intersection point between l.sub.1 and a perpendicular drawn from P.sub.max to l.sub.1 is P.sub.3, a middle point of a line segment P.sub.1P.sub.3 is P.sub.4, an intersection point between the curve and a straight line that passes through P.sub.4 and is perpendicular to l.sub.1 is P.sub.mid, a length of the line segment P.sub.1P.sub.3 is L, a length of a line segment P.sub.3P.sub.max is H, and a length of a line segment P.sub.4P.sub.max is h, (2 h/L)/(H/L) is 1.1 or more.