A process for additive manufacture of an article including conjoined first and second metals, wherein the first metal includes one of steel and titanium and the second metal includes another of the steel and the titanium. The process comprises arranging an interface layer of a third metal on a substrate of the first metal, wherein the third metal is capable of forming an alloy with the first metal and capable of forming an alloy with the second metal. The process further comprises supplying a consumable form of the second metal to a locus of the interface layer and heating the locus of the interface layer in an non-reactive environment. In this process, the heating fuses the consumable form of the second metal to render a fused form of the second metal and joins the fused form of the second metal to the interface layer.

A process for additive manufacture of an article including conjoined first and second metals, wherein the first metal includes one of steel and titanium and the second metal includes another of the steel and the titanium. The process comprises arranging an interface layer of a third metal on a substrate of the first metal, wherein the third metal is capable of forming an alloy with the first metal and capable of forming an alloy with the second metal. The process further comprises supplying a consumable form of the second metal to a locus of the interface layer and heating the locus of the interface layer in an non-reactive environment. In this process, the heating fuses the consumable form of the second metal to render a fused form of the second metal and joins the fused form of the second metal to the interface layer.

A method comprising the steps of: distributing a titanium alloy or pure titanium powder layer on a work table inside a vacuum chamber, directing at least one electron beam from at least one electron beam source over the work table causing the powder layer to fuse in selected locations, distributing a second powder layer on the work table of a titanium alloy or pure titanium inside the build chamber, directing the at least one electron beam over the work table causing the second powder layer to fuse in selected locations, and releasing a predefined concentration of the gas from the metal powder into the vacuum chamber when at least one of heating or fusing the metal powder layer, wherein at least one gas comprising hydrogen is absorbed into or chemically bonded to the titanium or titanium alloy powder to a concentration of 0.01-0.5% by weight of the hydrogen.

A method for forming a three-dimensional article through successive fusion of parts of a metal powder bed is provided, comprising the steps of: distributing a first metal powder layer on a work table inside a build chamber, directing at least one high energy beam from at least one high energy beam source over the work table causing the first metal powder layer to fuse in selected locations, distributing a second metal powder layer on the work table, directing at least one high energy beam over the work table causing the second metal powder layer to fuse in selected locations, introducing a first supplementary gas into the build chamber, which first supplementary gas comprising hydrogen, is capable of reacting chemically with or being absorbed by a finished three-dimensional article, and releasing a predefined concentration of the gas which had reacted chemically with or being absorbed by the finished three dimensional article.

A method for forming a three-dimensional article through successive fusion of parts of a metal powder bed is provided, comprising the steps of: distributing a first metal powder layer on a work table inside a build chamber, directing at least one high energy beam from at least one high energy beam source over the work table causing the first metal powder layer to fuse in selected locations, distributing a second metal powder layer on the work table, directing at least one high energy beam over the work table causing the second metal powder layer to fuse in selected locations, introducing a first supplementary gas into the build chamber, which first supplementary gas comprising hydrogen, is capable of reacting chemically with or being absorbed by a finished three-dimensional article, and releasing a predefined concentration of the gas which had reacted chemically with or being absorbed by the finished three dimensional article.

Described herein are compositions, methods, and systems for printing metal three-dimensional objects. In an example, described is a method of printing a three-dimensional object comprising: (i) depositing a metal powder build material, wherein the metal powder build material has an average particle size of from about 10 μm to about 250 μm; (ii) selectively applying a binder fluid on at least a portion of the metal powder build material, wherein the binder fluid comprises an aqueous liquid vehicle and latex polymer particles dispersed in the aqueous liquid vehicle; (iii) heating the selectively applied binder fluid on the metal powder build material to a temperature of from about 40° C. to about 180° C.; and (iv) repeating (i), (ii), and (iii) at least one time to form the three-dimensional object.

A method and an apparatus of a powder bed fusion additive manufacturing system that enables a quick change in the optical beam delivery size and intensity across locations of a print surface for different powdered materials while ensuring high availability of the system. A dynamic optical assembly containing a set of lens assemblies of different magnification ratios and a mechanical assembly may change the magnification ratios as needed. The dynamic optical assembly may include a transitional and rotational position control of the optics to minimize variations of the optical beam sizes across the print surface.

Various embodiments of the teachings herein include an additive manufacturing method. Some embodiments include: generating a model of a support member using a model of a printing member, wherein at least one portion of the support member is in contact with a lower part of the printing member, and a nitride layer is formed on a surface of the support member; introducing an inert gas into an additive manufacturing printing device, spreading a first material powder in a forming cylinder, performing laser scanning on the first powder using the model; and introducing an ammonia gas into the additive manufacturing printing device, spreading the first material powder in the forming cylinder in the additive manufacturing printing device, performing laser scanning on the first material powder, such that the first material powder is melted, and on the basis of the model of the support member, a nitride layer is formed.

Various embodiments of the teachings herein include an additive manufacturing method. Some embodiments include: generating a model of a support member using a model of a printing member, wherein at least one portion of the support member is in contact with a lower part of the printing member, and a nitride layer is formed on a surface of the support member; introducing an inert gas into an additive manufacturing printing device, spreading a first material powder in a forming cylinder, performing laser scanning on the first powder using the model; and introducing an ammonia gas into the additive manufacturing printing device, spreading the first material powder in the forming cylinder in the additive manufacturing printing device, performing laser scanning on the first material powder, such that the first material powder is melted, and on the basis of the model of the support member, a nitride layer is formed.

A lamination molding apparatus including a chamber covering a molding region; a laser beam source to emit a laser beam for sintering a material powder supplied on the molding region to form a sintered layer; and a scan unit to scan the laser beam. The laser beam has one or more spot shapes including at least an elongated shape, and the scan unit is configured to scan the laser beam, of which the spot shape is an elongated shape, in a lateral direction of the elongated shape, is provided.