The present disclosure provides a method for manufacturing a multi-main-phase structure magnet having excellent coercive force and a multi-main-phase structure magnet manufactured therefrom.

A multi-scale and multi-phase dispersion strengthened iron-based alloy, and preparation and characterization methods thereof are provided. The alloy contains a matrix and a strengthening phase. The strengthening phase includes at least two types of the strengthening phase particles with different sizes. A volume of the two types of the strengthening phase particles with different sizes having a particle size less than or equal to 50 nm accounts for 85-95% of a total volume of all the strengthening phase particles. The matrix is a Fe—Cr—W—Ti alloy. The strengthening phases include crystalline Y.sub.2O.sub.3 phase, Y—Ti—O phase, Y—Cr—O phase, and Y—W—O phase. The characterization method comprises electrolytically separating the strengthening phases in the alloy, and then characterizing by using an electron microscope. The tensile strength of the prepared alloy is more than 1600 MPa at room temperature, and is more than 600 MPa at 700° C.

A multi-scale and multi-phase dispersion strengthened iron-based alloy, and preparation and characterization methods thereof are provided. The alloy contains a matrix and a strengthening phase. The strengthening phase includes at least two types of the strengthening phase particles with different sizes. A volume of the two types of the strengthening phase particles with different sizes having a particle size less than or equal to 50 nm accounts for 85-95% of a total volume of all the strengthening phase particles. The matrix is a Fe—Cr—W—Ti alloy. The strengthening phases include crystalline Y.sub.2O.sub.3 phase, Y—Ti—O phase, Y—Cr—O phase, and Y—W—O phase. The characterization method comprises electrolytically separating the strengthening phases in the alloy, and then characterizing by using an electron microscope. The tensile strength of the prepared alloy is more than 1600 MPa at room temperature, and is more than 600 MPa at 700° C.

Disclosed are a method of manufacturing a uranium target, the method including (a) a step of preparing a conjugate including a matrix and a uranium target green compact formed in the matrix; and (b) a step of performing thermo-mechanical treatment through additional heat treatment at 530° C. to 600° C. during a hot rolling pass in a process of hot-rolling the conjugate, and a method of extracting radioactive Mo-99 using the uranium target.

Disclosed are a method of manufacturing a uranium target, the method including (a) a step of preparing a conjugate including a matrix and a uranium target green compact formed in the matrix; and (b) a step of performing thermo-mechanical treatment through additional heat treatment at 530° C. to 600° C. during a hot rolling pass in a process of hot-rolling the conjugate, and a method of extracting radioactive Mo-99 using the uranium target.

A method of producing a patterned composite metal plate includes a) providing at least two different metal and/or metal alloy powders, b) filling a container, b1) with the powders in different individual layers, or b2) making a three dimensional non-solid body of one of the powders, inserting said body in the container and filling the cavities in and around the said body completely with the other powder, c) sealing and evacuating the container, d) subjecting the container to hot isostatic pressing, e) optionally subjecting the consolidated body to hot deformation to form an intermediate body having a thickness of 50 to 200 mm, f) hot rolling the intermediate body in two perpendicular directions in order to form a plate, and optionally one or more of g) cold rolling the hot rolled plate to form a cold rolled plate h) slitting the plate and i) etching the plate.

A method of producing a patterned composite metal plate includes a) providing at least two different metal and/or metal alloy powders, b) filling a container, b1) with the powders in different individual layers, or b2) making a three dimensional non-solid body of one of the powders, inserting said body in the container and filling the cavities in and around the said body completely with the other powder, c) sealing and evacuating the container, d) subjecting the container to hot isostatic pressing, e) optionally subjecting the consolidated body to hot deformation to form an intermediate body having a thickness of 50 to 200 mm, f) hot rolling the intermediate body in two perpendicular directions in order to form a plate, and optionally one or more of g) cold rolling the hot rolled plate to form a cold rolled plate h) slitting the plate and i) etching the plate.

A syntactic metal foam composite that is substantially fully dense except for syntactic porosity is formed from a mixture of ceramic microballoons and matrix forming metal. The ceramic microballoons have a uniaxial crush strength and a much higher omniaxial crush strength. The mixture is continuously constrained while it is consolidated. The constraining force is less than the omniaxial crush strength. The substantially fully dense syntactic metal foam composite is then constrained and deformation worked at a substantially constant volume. The deformation working is typically performed at a yield strength that is adjusted by way of selecting a working temperature at which the yield strength is approximately less than the omniaxial crush strength of the included ceramic microballoons. This deformation causes at least work hardening and grain refinement in the matrix metal.

A syntactic metal foam composite that is substantially fully dense except for syntactic porosity is formed from a mixture of ceramic microballoons and matrix forming metal. The ceramic microballoons have a uniaxial crush strength and a much higher omniaxial crush strength. The mixture is continuously constrained while it is consolidated. The constraining force is less than the omniaxial crush strength. The substantially fully dense syntactic metal foam composite is then constrained and deformation worked at a substantially constant volume. The deformation working is typically performed at a yield strength that is adjusted by way of selecting a working temperature at which the yield strength is approximately less than the omniaxial crush strength of the included ceramic microballoons. This deformation causes at least work hardening and grain refinement in the matrix metal.

A method for preparing a nano spherical oxide dispersion strengthening phase using a micron oxide is proposed for the first time. First, a micron oxide is used as a raw material to prepare a nano oxide with a completely amorphous structure/matrix alloy composite powder by mechanical ball milling in stages. In the first stage, ball milling is performed, causing the oxide to break and transform in structure, and achieving nano-sizing and completely amorphization, to prepare a composite powder with a completely amorphous structure nano oxide uniformly distributed in the matrix alloy powder; and in the second stage, the composite powder obtained in the first stage and the remaining matrix alloy powder are uniformly mixed by ball milling. Then, the uniformly mixed powder is sequentially subjected to hot forming, hot rolling, and heat treatment, to obtain a nano spherical oxide dispersion strengthened alloy.