The present invention provides a gallium nitride sintered body and a gallium nitride molded article which have high density and low oxygen content without using a special apparatus. According to the first embodiment, a gallium nitride sintered body, which is characterized by having density of 2.5 g/cm.sup.3 to less than 5.0 g/cm.sup.3 and an intensity ratio of the gallium oxide peak of the (002) plane to the gallium nitride peak of the (002) plane of less than 3%, which is determined by X-ray diffraction analysis, can be obtained. According to the second embodiment, a metal gallium-impregnated gallium nitride molded article, which is characterized by comprising a gallium nitride phase and a metal gallium phase that exist as separate phases and having a molar ratio, Ga/(Ga+N), of 55% to 80%, can be obtained.

The present invention provides a metal-ceramic base material and the like which allow a ceramic base material and a desired metal material to be easily joined. A metal-ceramic base material (30) to be joined to a metal material (40), includes: a ceramic base material (20); and a metal film (25) provided on the ceramic base material (20), the metal film (25) being formed by thermal spray of a mixed powder material containing aluminum, alumina, and nickel, at least part of the nickel being exposed on a surface of the metal film (25).

A turbine component assembly is disclosed, including a first component, a second component, and an interface shield. The first component is arranged to be disposed adjacent to a hot gas path, and includes a ceramic matrix composite composition. The second component is adjacent to the first component and arranged to be disposed distal from the hot gas path across the first component. The interface shield is disposed on a contact region of the first component, and directly contacts the second component.

A unitary ceramic component is provided that includes a first ceramic component; a second ceramic component; and a series-hybrid joint coupling the first ceramic component to the second ceramic component. The series-hybrid joint includes a first bonding interface coupling the first ceramic component and the second ceramic component and a second bonding interface coupling the first ceramic component and the second ceramic component. The first bonding interface exhibits properties that are different from the second bonding interface.

A silicon carbide seed crystal includes a first silicon carbide substrate, a second silicon carbide substrate, a metal layer, and a first adhesion layer. The first silicon carbide substrate has a carbon surface and a silicon surface opposite to each other; the second silicon carbide substrate has a carbon surface and a silicon surface opposite to each other, in which the carbon surface of the second silicon carbide substrate is a surface utilized for crystal growth. The metal layer is disposed between the silicon surface of the second silicon carbide substrate and the silicon surface of the first silicon carbide substrate, and the first adhesion layer is disposed between the silicon surface of the first silicon carbide substrate and the metal layer, in which a material of the first adhesion layer has a property of easily forming silicide with silicon.

In a step (a), a guard ring is disposed on a ceramic substrate (a second member) such that one of openings of a through hole of the guard ring is covered with a joint surface of the ceramic substrate. In a step (b), a brazing material made of a metal, a powder made of a material having a smaller thermal expansion coefficient than the brazing material, and a feeding terminal are inserted into the through hole. In a step (c), the brazing material is fused to impregnate the powder with the brazing material to thereby form a joint layer including the brazing material and the powder. In this manner, the joint surface and the joint surface are joined to each other through the joint layer.

A precipitation-hardened partial transient liquid phase bond and method of making same is provided. The bond is created at a bonding temperature and then, based on the phase diagrams corresponding to the materials in the interlayer between the bonded materials, the bond is held at a lower heat-treatment temperature to achieve a precipitation-hardened structure.

After a copper plate 14 is bonded to at least one surface of a ceramic substrate 10 via an active metal containing brazing filler metal 12 which contains silver, the unnecessary portion of the copper plat 14 and active metal containing brazing filler metal 12 is removed, and thereafter, an unnecessary portion of the copper plate 14 is removed by chemical polishing so as to cause the active metal containing brazing filler metal 12 to protrude from the side face portion of the copper plate 14, and then, a silver layer 18 adhered to the surface of the copper plate 14 by the chemical polishing is removed.

A hybrid component (45) is provided including a plurality of laminates (10) stacked on one another to define a stacked laminate structure (58). The laminates (10) include a ceramic matrix composite material (22) and at least one opening (24) defined therein. A metal support structure (56) may be additively manufactured through each opening (24) so as to extend through the stacked laminate structure (58).

A bonding target member 1 having a solid bonding material 3 with aluminum as a main component is interposed between a metal member 2 and a ceramic member 4 and an elastic member 12 are pressurized by a pressurizing section 13 and a bonding tool section 15 of a resonator 14 in a vertical direction. The bonding tool section 15 of the resonator 14 resonates with sound vibration or ultrasound vibration transmitted from an oscillator 16. An interfacial portion between the metal member 2 and the bonding material 3 with aluminum as a main component and an interfacial portion between the bonding material 3 with aluminum as a main component and the ceramic member 4 each receive pressurization and vibration energy to be bonded together. The metal member 2 and the ceramic member 4 can be bonded together at ordinary temperature in the atmosphere with the bonding material 3 with aluminum as a main component. When the ceramic member 4 has a thickness resistant to pressurization and vibration energy at the time of bonding to resist crack, the elastic member 12 may be disposed on a metal member 2 side, or may not be used.