The present invention discloses a method for manufacturing a thin-walled metal component by three-dimensional (3D) printing and hot gas bulging. The present invention uses 3D printing to obtain a complex thin-walled preform, which reduces a deformation during subsequent hot gas bulging. The present invention avoids local bulging thinning and cracking, undercuts at the parting during die closing, and wrinkles due to the uneven distribution of cross-sectional materials, etc. The present invention obtains a high accuracy in the form and dimension through hot gas bulging. After a desired shape is obtained by hot gas bulging, a die is closed to keep the component under high temperature and high pressure for a period of time, so that a grain and a phase of the material are transformed to form a desired microstructure.

The present invention discloses a method for manufacturing a thin-walled metal component by three-dimensional (3D) printing and hot gas bulging. The present invention uses 3D printing to obtain a complex thin-walled preform, which reduces a deformation during subsequent hot gas bulging. The present invention avoids local bulging thinning and cracking, undercuts at the parting during die closing, and wrinkles due to the uneven distribution of cross-sectional materials, etc. The present invention obtains a high accuracy in the form and dimension through hot gas bulging. After a desired shape is obtained by hot gas bulging, a die is closed to keep the component under high temperature and high pressure for a period of time, so that a grain and a phase of the material are transformed to form a desired microstructure.

A method for making small diameter NiTi metal alloy components, including balls, comprising providing a metal powder comprising nickel, titanium, and a transition metal, consolidating the metal powder into cylindrical rods, and cutting the cylindrical rods into segments. The segments are then machined into spheres slightly larger than the finished ball size diameter. The spheres are heat treated to solutionize and dissolve all phases and subsequently cooled without the need for rapid quenching due to the influence of the transition metal to suppresses the formation of soft phases in the spheres, wherein such soft phases prevent hardening, to achieve a Rockwell hardness of HRC 58-62. Finally, the hardened spheres are polished until the desired finished ball size diameter and surface finish is achieved.

A method for making small diameter NiTi metal alloy components, including balls, comprising providing a metal powder comprising nickel, titanium, and a transition metal, consolidating the metal powder into cylindrical rods, and cutting the cylindrical rods into segments. The segments are then machined into spheres slightly larger than the finished ball size diameter. The spheres are heat treated to solutionize and dissolve all phases and subsequently cooled without the need for rapid quenching due to the influence of the transition metal to suppresses the formation of soft phases in the spheres, wherein such soft phases prevent hardening, to achieve a Rockwell hardness of HRC 58-62. Finally, the hardened spheres are polished until the desired finished ball size diameter and surface finish is achieved.

A sintered body manufacturing apparatus includes a compacting apparatus configured to press a raw powder containing a metal powder into a green compact, a machining apparatus configured to perform a cutting operation on the green compact to produce an unsintered materials, and a green compact conveying path configured to connect the compacting apparatus in series to the machining apparatus to convey green compacts one by one from the compacting apparatus to the machining apparatus.

A gear includes a sintered body, in which Fe is contained as a principal component, Ni is contained in a proportion of 2 mass % or more and 20 mass % or less, Si is contained in a proportion of 0.3 mass % or more and 5.0 mass % or less, C is contained in a proportion of 0.005 mass % or more and 0.3 mass % or less, and one element selected from the group consisting of Ti, V, Y, Zr, Nb, Hf, and Ta is defined as a first element, that is contained in a proportion of 0.01 mass % or more and 0.7 mass % or less.

A method for manufacturing a sintered member includes a step of preparing a raw material powder containing an iron-based powder; a step of forming a green compact having a relative density of 97% or more and having a solid cylindrical shape or hollow cylindrical shape by compacting the raw material powder; and a step of sintering the green compact. The raw material powder contains at least one of a mixed powder containing pure iron powder and Ni powder and an iron alloy powder containing Ni as an additive element. The total amount of the Ni powder and Ni serving as the additive element in the raw material powder is 1 mass % or more.

A sliding member includes an overlay formed with an alloy plated film of Bi and Sb, the Sb concentration increasing in the overlay with the depth from the surface of the overlay.

A sliding member includes an overlay formed with an alloy plated film of Bi and Sb, the Sb concentration increasing in the overlay with the depth from the surface of the overlay.

A composite body has a cermet member, a metal member and an intermediate member. The cermet member includes a cermet oxide phase and a cermet metal phase. The cermet oxide phase contains a Ni-containing oxide or an Fe-containing oxide. The cermet metal phase contains Ni. The intermediate layer contains Cu. The mass proportions of Cu in the cermet metal phase at points which are spaced apart by 10, 50, 100 and 1000 μm from the interface between the cermet member and the intermediate layer to the cermet member side are denoted by C10, C50, C100 and C1000 (mass %). When the mass proportions of Cu in the cermet oxide phase at points which are spaced apart by 10 and 100 μm from the interface to the cermet member side are denoted by M10 and M100 (mass %), C10>C50>C100>C1000, and 5>M10−M100>−5.