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 additively manufactured (AM) object may include a body including an opening in an exterior surface thereof, the opening having a shape and a first area at the exterior surface of the body. A mask may be positioned over the opening. The mask has the shape of the opening and a second area that is larger than the first area so as to overhang the exterior surface of the body about the opening. A plurality of support ligaments couple to the mask and the exterior surface of the body at a location adjacent to the opening to support a portion of the mask. A coating can be applied to the object, and the mask removed. The final AM object includes a plurality of ligament elements extending from the exterior surface of the body and through the coating adjacent the opening, each ligament element at least partially surrounded by the coating.

An additively manufactured (AM) object may include a body including an opening in an exterior surface thereof, the opening having a shape and a first area at the exterior surface of the body. A mask may be positioned over the opening. The mask has the shape of the opening and a second area that is larger than the first area so as to overhang the exterior surface of the body about the opening. A plurality of support ligaments couple to the mask and the exterior surface of the body at a location adjacent to the opening to support a portion of the mask. A coating can be applied to the object, and the mask removed. The final AM object includes a plurality of ligament elements extending from the exterior surface of the body and through the coating adjacent the opening, each ligament element at least partially surrounded by the coating.

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.

Methods for repairing an airfoil having a damaged region are provided. The method can include removing the damaged portion from the airfoil to form an intermediate component. The damaged portion generally includes an original film hole having an original cross-sectional geometry. Using additive manufacturing, a replacement portion is then applied on the intermediate component to form a repaired component with the replacement portion including a rebuilt film hole having a rebuilt cross-sectional geometry that is different than the original cross-sectional geometry.

Methods for repairing an airfoil having a damaged region are provided. The method can include removing the damaged portion from the airfoil to form an intermediate component. The damaged portion generally includes an original film hole having an original cross-sectional geometry. Using additive manufacturing, a replacement portion is then applied on the intermediate component to form a repaired component with the replacement portion including a rebuilt film hole having a rebuilt cross-sectional geometry that is different than the original cross-sectional geometry.

An additive-coated sheave assembly having a wheel with a groove in an outer circumferential surface of the wheel. The additive-coated sheave assembly can have an axle configured to support the wheel and a frame configured to receive and support the axle. A coating can be affixed to the groove by an additive manufacturing process. A method of manufacturing a sheave by coating the groove with a coating by an additive manufacturing process is also disclosed.

An additive-coated sheave assembly having a wheel with a groove in an outer circumferential surface of the wheel. The additive-coated sheave assembly can have an axle configured to support the wheel and a frame configured to receive and support the axle. A coating can be affixed to the groove by an additive manufacturing process. A method of manufacturing a sheave by coating the groove with a coating by an additive manufacturing process is also disclosed.

A method includes additively manufacturing an article in an inert environment, removing the article from the inert environment and placing the article in a non-inert environment, allowing at least a portion the article to oxidize in the non-inert environment to form an oxidized layer on a surface of the article, and removing the oxidized layer (e.g., to smooth the surface of the article). The method can further include relieving stress in the article (e.g., via heating the article after additive manufacturing).