The present invention relates to alloy compositions for 3D metal printing procedures which provide metallic parts with high hardness, tensile strengths, yield strengths, and elongation. The alloys include Fe, Cr and Mo and at least three or more elements selected from C, Ni, Cu, Nb, Si and N. As built parts indicate a tensile strength of at least 1000 MPa, yield strength of at least 640 MPa, elongation of at least 3.0% and hardness (HV) of at least 375.

The present invention relates to alloy compositions for 3D metal printing procedures which provide metallic parts with high hardness, tensile strengths, yield strengths, and elongation. The alloys include Fe, Cr and Mo and at least three or more elements selected from C, Ni, Cu, Nb, Si and N. Ni may be replaced with Mn. As built parts indicate a tensile strength of at least 1000 MPa, yield strength of at least 640 MPa, elongation of at least 3.0% and hardness (HV) of at least 375.

A vibration isolator assembly includes a bellows component, a piston component, a shaft component, and a housing component, wherein at least one of the bellows component, the piston component, the shaft component, and the housing component is formed using additive manufacturing techniques.

A method for removing powder from a component or part produced by metal additive manufacturing systems based on powder beds. The method includes manufacturing a part by additive manufacturing, the part having at least one internal cavity with at least one external opening. The internal cavity is at least partly filled with powder, the powder in the internal cavity having grains agglomerated or connected to each other. The method further including: evacuating gas from the internal cavity; adding liquid electrolyte to the internal cavity, and using an electrochemical process for separating connected powder grains in the cavity.

A method for removing powder from a component or part produced by metal additive manufacturing systems based on powder beds. The method includes manufacturing a part by additive manufacturing, the part having at least one internal cavity with at least one external opening. The internal cavity is at least partly filled with powder, the powder in the internal cavity having grains agglomerated or connected to each other. The method further including: evacuating gas from the internal cavity; adding liquid electrolyte to the internal cavity, and using an electrochemical process for separating connected powder grains in the cavity.

Disclosed is a method for preparing a rare-earth permanent magnet. The method includes: preparing an R-T-B-based sintered magnet; applying a first mixture including a light rare-earth element onto the surface of the R-T-B-based sintered magnet and diffusing the first mixture under a vacuum atmosphere to prepare a light rare-earth permanent magnet having the light rare-earth element diffused into a grain boundary; and applying a second mixture including a heavy rare-earth element onto the surface of the light rare-earth permanent magnet and diffusing the second mixture into the grain-boundary under a vacuum atmosphere to prepare a rare-earth permanent magnet.

Disclosed is a method for preparing a rare-earth permanent magnet. The method includes: preparing an R-T-B-based sintered magnet; applying a first mixture including a light rare-earth element onto the surface of the R-T-B-based sintered magnet and diffusing the first mixture under a vacuum atmosphere to prepare a light rare-earth permanent magnet having the light rare-earth element diffused into a grain boundary; and applying a second mixture including a heavy rare-earth element onto the surface of the light rare-earth permanent magnet and diffusing the second mixture into the grain-boundary under a vacuum atmosphere to prepare a rare-earth permanent magnet.

An apparatus and method for removing support material from and/or smoothing surfaces of an additively manufactured part (the AM part) is disclosed. The apparatus may include a chamber, a support surface within the chamber, and one or more nozzles within the chamber. The nozzles may be the same size or different sizes. The support surface may be configured to support the AM part. The support surface may have one or more openings sized and configured to allow the fluid to pass through the opening(s). The nozzles may be configured to spray a fluid at the AM part, and the spray may be an atomized or semi-atomized spray of the fluid.

A powder feed for injection molding process includes a first metal powder, and a second metal powder. The first metal powder and the second metal powder are mixed together evenly. The second metal powder has a mass percentage of about less than 10% of a total mass of the powder feed for injection molding process. The first metal powder is resistant to the corrosion by a chemical reagent, and the second metal powder is corrodible in the chemical reagent.

A polishing method for an inner wall of a hollow metal part, including: firstly, placing a coaxial cathode in an inner hole of a metal part when a metal part model is designed, and printing the metal part model and the coaxial cathode together; then, sealing two ends of an inner hole cavity of the metal part by using a light curing part, fixing the coaxial cathode, filling the cavity with a polishing solution, and performing polishing treatment by using an electrochemical polishing method; and finally, reversing an electrode to break the coaxial cathode and take out the broken coaxial cathode to obtain a polished metal part. The polishing of a complex-shaped inner hole of a 3D-printed metal part is realized, the defect that an inner hole of a 3D-printed metal part with a complex-shaped hollow part cannot be polished by using a traditional machining method is overcome, the problem that an inner wall of a metal part polished by using an electrochemical method is non-uniform is solved, the surface quality of the inner hole of the 3D-printed metal part with the complex-shaped hollow part is improved, and the application prospect and postprocessing technology of the 3D-printed metal part are expanded.