This method for producing porous sintered aluminum includes: mixing aluminum powder with a sintering aid powder containing titanium to obtain a raw aluminum mixed powder; mixing the raw aluminum mixed powder with a water-soluble resin binder, water, and a plasticizer containing at least one selected from polyhydric alcohols, ethers, and esters to obtain a viscous composition; drying the viscous composition in a state where air bubbles are mixed therein to obtain a formed object prior to sintering; and heating the formed object prior to sintering in a non-oxidizing atmosphere, wherein when a temperature at which the raw aluminum mixed powder starts to melt is expressed as Tm (° C.), a temperature T (° C.) of the heating fulfills Tm−10 (° C.)≤T≤685 (° C.).

A powder for molding is a mixture of first constituent particles, which are made up of first metal base particles, and second constituent particles, which are made up of second metal base particles. A first lubricant concentration that is a mass proportion of a first internal lubricant adhered to the surface of the first metal base particles with respect to the total of the first constituent particles, is greater than a second lubricant concentration that is a mass proportion of a second internal lubricant that is adhered to the surface of the second metal base particles with respect to the total of the second constituent particles.

In at least one embodiment, a hybrid permanent magnet is disclosed. The magnet may include a plurality of anisotropic regions of a Nd—Fe—B alloy and a plurality of anisotropic regions of a MnBi alloy. The regions of Nd—Fe—B alloy and MnBi alloy may be substantially homogeneously mixed within the hybrid magnet. The regions of Nd—Fe—B and MnBi may have the same or a similar size. The magnet may be formed by homogeneously mixing anisotropic powders of MnBi and Nd—Fe—B, aligning the powder mixture in a magnetic field, and consolidating the powder mixture to form an anisotropic hybrid magnet. The hybrid magnet may have improved coercivity at elevated temperatures, while still maintaining high magnetization.

In at least one embodiment, a hybrid permanent magnet is disclosed. The magnet may include a plurality of anisotropic regions of a Nd—Fe—B alloy and a plurality of anisotropic regions of a MnBi alloy. The regions of Nd—Fe—B alloy and MnBi alloy may be substantially homogeneously mixed within the hybrid magnet. The regions of Nd—Fe—B and MnBi may have the same or a similar size. The magnet may be formed by homogeneously mixing anisotropic powders of MnBi and Nd—Fe—B, aligning the powder mixture in a magnetic field, and consolidating the powder mixture to form an anisotropic hybrid magnet. The hybrid magnet may have improved coercivity at elevated temperatures, while still maintaining high magnetization.

The present disclosure provides a radially oriented solid cylindrical magnet, a method and device for molding and manufacturing the same, and a rotor and motor component using the same. The radial orientation degree of the solid cylindrical magnet is greater than or equal to 90%. A mold includes no mold core. Magnetic particles in the mold are continuously rotated in a magnetic field during molding, and an oriented magnetic field is applied during molding. The manufactured solid cylindrical magnet can be directly used as a rotor of a micro-motor to replace a conventional rotor with a radially oriented magnet ring, or can be used for producing radially oriented magnet rings with an arbitrary inner diameter, so as to obtain radially oriented magnet rings having an inner diameter less than 3 mm or even less for micro-motors.

The present disclosure provides a radially oriented solid cylindrical magnet, a method and device for molding and manufacturing the same, and a rotor and motor component using the same. The radial orientation degree of the solid cylindrical magnet is greater than or equal to 90%. A mold includes no mold core. Magnetic particles in the mold are continuously rotated in a magnetic field during molding, and an oriented magnetic field is applied during molding. The manufactured solid cylindrical magnet can be directly used as a rotor of a micro-motor to replace a conventional rotor with a radially oriented magnet ring, or can be used for producing radially oriented magnet rings with an arbitrary inner diameter, so as to obtain radially oriented magnet rings having an inner diameter less than 3 mm or even less for micro-motors.

Power transmission members, such as synchronous joint members, are each formed by sintering a compact which is molded from a mixture containing metal powder and a binder, as an injection material, by metal powder injection molding. Flow promotion recesses configured to facilitate a flow of the mixture to areas corresponding to power transmission surfaces or the like when the compact is molded are formed in each of two side surfaces of each power transmission member.

Power transmission members, such as synchronous joint members, are each formed by sintering a compact which is molded from a mixture containing metal powder and a binder, as an injection material, by metal powder injection molding. Flow promotion recesses configured to facilitate a flow of the mixture to areas corresponding to power transmission surfaces or the like when the compact is molded are formed in each of two side surfaces of each power transmission member.

Embodiments can relate to an improved hydroflux, additive or electroless plating assisted densification cold sintering process to densify powdered metals at lower compaction pressures and lower temperatures (e.g., 520 MPa and 140° C.). The process can involve inducing dissolution precipitation mechanisms at powder interfaces by introducing a transport phase (formed by the introduction of water during the process to suppress melting temperatures) that is not an aqueous solution. Particle interfaces in the cold sinter fuse together by the presence of the additional transport phase, thereby reducing the temperatures and pressures needed for compaction. Some embodiments involve the use of elements to form a eutectic at the desired low temperature, thereby stabilizing certain crystal structure shapes of isometric crystal systems, inducing rapid densification, and facilitating pore smoothing. Embodiments of the process can be used to generate a green compact via sintering that exhibits improved green strength.

Embodiments can relate to an improved hydroflux, additive or electroless plating assisted densification cold sintering process to densify powdered metals at lower compaction pressures and lower temperatures (e.g., 520 MPa and 140° C.). The process can involve inducing dissolution precipitation mechanisms at powder interfaces by introducing a transport phase (formed by the introduction of water during the process to suppress melting temperatures) that is not an aqueous solution. Particle interfaces in the cold sinter fuse together by the presence of the additional transport phase, thereby reducing the temperatures and pressures needed for compaction. Some embodiments involve the use of elements to form a eutectic at the desired low temperature, thereby stabilizing certain crystal structure shapes of isometric crystal systems, inducing rapid densification, and facilitating pore smoothing. Embodiments of the process can be used to generate a green compact via sintering that exhibits improved green strength.