A method for preparing prefabricated gas pore defects includes: defining a defect area, defining a volume percentage of the gas pore defects in the defect area, adjusting the proportion of satellite powder, the proportion of hollow powder and the process parameters of defect preparation according to the volume percentage of the gas pore defects, based on the technique of laser melting deposition, printing the defect area layer by layer by using the defect preparation powder and the process parameters of defect preparation, wherein the particle size of the defect preparation powder is between 45 μm and 106 μm, the proportion of satellite powder is 55-65% and the proportion of hollow powder is 2.9-3.1%, the process parameters of defect preparation comprises: laser power of 600W-1000W, scanning rate of 400 mm/min-800 mm/min, powder feeding rate of 12 g/min-20 g/min, spot diameter of 1 mm-2 mm, scanning spacing of 0.5 mm-1 mm and layer thickness of 0.15 mm-0.2 mm.

A method for preparing prefabricated gas pore defects includes: defining a defect area, defining a volume percentage of the gas pore defects in the defect area, adjusting the proportion of satellite powder, the proportion of hollow powder and the process parameters of defect preparation according to the volume percentage of the gas pore defects, based on the technique of laser melting deposition, printing the defect area layer by layer by using the defect preparation powder and the process parameters of defect preparation, wherein the particle size of the defect preparation powder is between 45 μm and 106 μm, the proportion of satellite powder is 55-65% and the proportion of hollow powder is 2.9-3.1%, the process parameters of defect preparation comprises: laser power of 600W-1000W, scanning rate of 400 mm/min-800 mm/min, powder feeding rate of 12 g/min-20 g/min, spot diameter of 1 mm-2 mm, scanning spacing of 0.5 mm-1 mm and layer thickness of 0.15 mm-0.2 mm.

An object of the present invention is to provide an additive manufactured object which is free of solidification cracking due to, e.g., heat shrinkage during additive manufacturing of an aluminum alloy; which is free of anisotropy in strength, and has high strength and ductility. An aluminum alloy powder for additive manufacturing includes aluminum alloy particles in which not less than 0.01% by mass and not more than 1% by mass of a grain refiner is trapped. This grain refiner is at least one selected from the borides and carbides of group 4 elements.

An object of the present invention is to provide an additive manufactured object which is free of solidification cracking due to, e.g., heat shrinkage during additive manufacturing of an aluminum alloy; which is free of anisotropy in strength, and has high strength and ductility. An aluminum alloy powder for additive manufacturing includes aluminum alloy particles in which not less than 0.01% by mass and not more than 1% by mass of a grain refiner is trapped. This grain refiner is at least one selected from the borides and carbides of group 4 elements.

In one example in accordance with the present disclosure, a system is described. The system includes a hot isostatic pressing system. The hot isostatic pressing system includes a pressure vessel to receive an additively manufactured 3D steel object and a pressure source to apply isostatic pressure to the 3D steel object disposed therein. The isostatic pressing system also includes a heater to heat the 3D steel object while in the pressure vessel. The system also includes a controller. The controller 1) determines characteristics of the 3D steel object, 2) determines, a temperature, pressure, and duration for isostatically treating the 3D steel object, and 3) activates the pressure source and heater to apply a determined pressure and temperature to the 3D steel object based on determined characteristics of the 3D steel object.

Provided are a laminate shaped article made of a maraging steel and having excellent toughness, a method for manufacturing the same, and a metal powder for laminate shaping. The laminate shaped article is made of a maraging steel comprising 0.1-5.0 mass % of Ti. When sis is performed on concentration distribution of Ti in a cross section parallel to a lamination direction of the above laminate shaped article, a length of a linear Ti-rich portion having a Ti concentration B of (1.5×A) or more with respect to an average Ti concentration A in the cross section is 15 μm or less. In addition, the method for manufacturing the laminate shaped article uses a metal powder made of a maraging steel comprising 0.1-5.0 mass % of Ti, and a heat source output is set to 50-330 W and a scanning speed is set to 480-3000 mm/sec during the laminate shaping.

A process control system and a method for process control of a solid-state additive manufacturing system capable of performing various additive processes, such as joining, additive manufacturing, coating, repair and others, are disclosed. The process control system is capable of simultaneous measuring, monitoring and controlling multiple process variables, viz. material temperature, actuator down force, tool force (or torque), tool position, tool angular and transverse velocity, spindle torque (angular velocity), filler flow rate, filler composition, track width, inert gas flow rate and others. A feeding system for continuous supply of filler material to the solid-state additive manufacturing system is also disclosed. The filler material can be in a form of a powder, granules, briquettes, beads, flakes, wires, rods, films, scrap pieces, sheets, blocks or their combinations. Methods for generation of different periodic and non-periodic structures and joints using the process-controlled solid-state additive manufacturing system are also disclosed.

A process control system and a method for process control of a solid-state additive manufacturing system capable of performing various additive processes, such as joining, additive manufacturing, coating, repair and others, are disclosed. The process control system is capable of simultaneous measuring, monitoring and controlling multiple process variables, viz. material temperature, actuator down force, tool force (or torque), tool position, tool angular and transverse velocity, spindle torque (angular velocity), filler flow rate, filler composition, track width, inert gas flow rate and others. A feeding system for continuous supply of filler material to the solid-state additive manufacturing system is also disclosed. The filler material can be in a form of a powder, granules, briquettes, beads, flakes, wires, rods, films, scrap pieces, sheets, blocks or their combinations. Methods for generation of different periodic and non-periodic structures and joints using the process-controlled solid-state additive manufacturing system are also disclosed.

In various embodiments, a water-based binder solution for use in additive manufacturing, includes a thermoplastic binder. The thermoplastic binder includes a first polymer strand having a weight average molecular weight (Mw) of from greater than or equal to 5,000 g/mol to less than or equal to 15,000 g/mol, a second polymer strand having a weight average molecular weight of from greater than or equal to 10,000 g/mol to less than or equal to 50,000 g/mol, and a third polymer strand having a weight average molecular weight of from greater than or equal to 1,000 g/mol to less than or equal to 5,000 g/mol. The binder solution further comprises from greater than or equal to 0.1 wt % to less than or equal to 5 wt % of a non-aqueous solvent having a boiling point of greater than 100° C.

In various embodiments, a water-based binder solution for use in additive manufacturing, includes a thermoplastic binder. The thermoplastic binder includes a first polymer strand having a weight average molecular weight (Mw) of from greater than or equal to 5,000 g/mol to less than or equal to 15,000 g/mol, a second polymer strand having a weight average molecular weight of from greater than or equal to 10,000 g/mol to less than or equal to 50,000 g/mol, and a third polymer strand having a weight average molecular weight of from greater than or equal to 1,000 g/mol to less than or equal to 5,000 g/mol. The binder solution further comprises from greater than or equal to 0.1 wt % to less than or equal to 5 wt % of a non-aqueous solvent having a boiling point of greater than 100° C.