An additive manufacturing apparatus includes: a material supply unit that supplies a build material to a process area of an additive target surface; an irradiation unit that irradiates the process area with a laser beam that melts the build material; and a control device that controls the material supply unit and the irradiation unit for creating at least a part of an object using a dot-shaped bead, the dot-shaped bead being formed of the build material melted by radiation of the laser beam. The additive manufacturing apparatus can improve the shape accuracy of the object.

A method of joining first and second component bodies comprises: cold-spraying a first joining surface of the first component body with a bond material which is harder than the first joining surface; cold-spraying a second joining surface of the second component body with the bond material; and joining the first and second component bodies by way of the first joining surface.

A method of joining first and second component bodies comprises: cold-spraying a first joining surface of the first component body with a bond material which is harder than the first joining surface; cold-spraying a second joining surface of the second component body with the bond material; and joining the first and second component bodies by way of the first joining surface.

A method for the preparation of steel sheets for fabricating a welded steel blank is provided. The method includes procuring at least two pre-coated steel sheets, each having a pre-coating of an intermetallic alloy layer, topped by a layer of aluminum metal or aluminum alloy or aluminum-based alloy. The sheets have a principal face, an opposite principal face, and at least one secondary face. The sheets are positioned so a gap between 0.02 and 2 mm exists between the secondary faces. The secondary faces face each other. The positioning of the first and second sheets defines a median plane perpendicular to the principal faces. Layers of metal alloy are removed by melting and vaporization simultaneously on the principal faces, in a peripheral zone of the sheets, the peripheral zones being the zones of the principal faces closest in relation to the median plane.

A method for the preparation of steel sheets for fabricating a welded steel blank is provided. The method includes procuring at least two pre-coated steel sheets, each having a pre-coating of an intermetallic alloy layer, topped by a layer of aluminum metal or aluminum alloy or aluminum-based alloy. The sheets have a principal face, an opposite principal face, and at least one secondary face. The sheets are positioned so a gap between 0.02 and 2 mm exists between the secondary faces. The secondary faces face each other. The positioning of the first and second sheets defines a median plane perpendicular to the principal faces. Layers of metal alloy are removed by melting and vaporization simultaneously on the principal faces, in a peripheral zone of the sheets, the peripheral zones being the zones of the principal faces closest in relation to the median plane.

A metal-joining structure (100) includes: an iron alloy part (1); an aluminum alloy part (2); and a joining interface layer (3) provided between the iron alloy part (1) and the aluminum alloy part (2). The joining interface layer (3) includes: an iron-silicon solid-solution-phase sublayer (4) in contact with the iron alloy part (1); an aluminum-silicon eutectic-phase sublayer (5) in contact with the aluminum alloy part (2); and a silicon sublayer (6) provided between the iron-silicon solid-solution-phase sublayer (4) and the aluminum-silicon eutectic-phase sublayer (5).

A metal-joining structure (100) includes: an iron alloy part (1); an aluminum alloy part (2); and a joining interface layer (3) provided between the iron alloy part (1) and the aluminum alloy part (2). The joining interface layer (3) includes: an iron-silicon solid-solution-phase sublayer (4) in contact with the iron alloy part (1); an aluminum-silicon eutectic-phase sublayer (5) in contact with the aluminum alloy part (2); and a silicon sublayer (6) provided between the iron-silicon solid-solution-phase sublayer (4) and the aluminum-silicon eutectic-phase sublayer (5).

A laser-welded assembly of opposing sheets of ceramic and glass, ceramic, or glass-ceramic compositions comprises an intervening bonding layer having a thickness dimension that separates the opposing sheets by less than about 1000 nm. Each of the opposing sheets has a thickness dimension at least about 20 times the thickness dimension of the intervening bonding layer. The intervening bonding layer has a melting point greater than that of one or both of the opposing sheets. The ceramic sheet is a pass-through sheet with a composite T/R spectrum comprising a portion that lies below about 30% across a target irradiation band residing at or above about 1400 nm and at or below about 4500 nm wavelength. The intervening bonding layer has an absorption spectrum comprising a portion that lies above about 80% across the target irradiation band. The assembly comprises a weld bonding the opposing surfaces of the opposing sheets.

A laser-welded assembly of opposing sheets of ceramic and glass, ceramic, or glass-ceramic compositions comprises an intervening bonding layer having a thickness dimension that separates the opposing sheets by less than about 1000 nm. Each of the opposing sheets has a thickness dimension at least about 20 times the thickness dimension of the intervening bonding layer. The intervening bonding layer has a melting point greater than that of one or both of the opposing sheets. The ceramic sheet is a pass-through sheet with a composite T/R spectrum comprising a portion that lies below about 30% across a target irradiation band residing at or above about 1400 nm and at or below about 4500 nm wavelength. The intervening bonding layer has an absorption spectrum comprising a portion that lies above about 80% across the target irradiation band. The assembly comprises a weld bonding the opposing surfaces of the opposing sheets.

A laser welding method and a laser welding apparatus capable of preventing formation of blowholes and obtaining an excellent welled state are provided. An embodiment is a laser welding method for a component to be welded 40 including a third metal component 40c sandwiched between first and second metal components 40a and 40b, in which the metal components are welded to each other by scanning a laser beam in a first direction perpendicular to a direction in which the third metal component 40c is sandwiched, in which a welded part 42 is formed by applying a first laser beam 12a while scanning it in the first direction and thereby melting and then solidifying the component to be welded 40.