A Sm—Fe—N-based rare earth magnet more resistant to demagnetization than ever before, particularly at high temperatures, and a production method thereof are provided.

The present disclosure presents a production method of a rare earth magnet, including mixing a SmFeN magnetic powder and a modifier powder to obtain a mixed powder, compression-molding the mixed powder in a magnetic field to obtain a magnetic-field molded body, pressure-sintering the magnetic-field molded body to obtain a sintered body, and heat-treating the sintered body, and a rare earth magnet obtained by the method. D.sub.50 of the magnetic powder is 1.50 μm or more and 3.00 μm or less, the content ratio of the zinc component in the modifier powder is 6 mass % or more and 30 mass % or less, and the heat treatment temperature is 350° C. or more and 410° C. or less.

The present invention provides a method of in situ 4D printing of high-temperature materials including 3D printing a structure of an ink including a precursor. The structure is treated with controlled high energy flow to create a portion which has a different coefficient of thermal expansion/thermal shrinkage ratio. The structure is heated and the difference in the coefficient of thermal expansion creates an interface stress to cause a selected level of deformation. Alternatively, two structures with different coefficients of expansion/thermal shrinkage ratio may be printed. Thermal treatment of the two structures creates an interface stress to cause a selected level of deformation.

A method for producing a sintered member, including the steps of: preparing a raw powder; press-forming the raw powder to produce a green compact; and sintering the green compact by high-frequency induction heating, wherein a temperature of the green compact in the sintering step is controlled to satisfy all the following conditions (I) to (III): (I) the temperature is increased without maintaining the temperature in a temperature range equal to or higher than an A.sub.1 point of an Fe—C phase diagram and lower than the sintering temperature of the green compact, (II) a heating rate is set to 12° C./s or more in a temperature range of the A.sub.1 point to an A.sub.3 point of the Fe—C phase diagram, and (III) a heating rate is set to 4° C./s or more in a temperature range of the A.sub.3 point of the Fe—C phase diagram to the sintering temperature of the green compact.

A method for producing a sintered member, including the steps of: preparing a raw powder; press-forming the raw powder to produce a green compact; and sintering the green compact by high-frequency induction heating, wherein a temperature of the green compact in the sintering step is controlled to satisfy all the following conditions (I) to (III): (I) the temperature is increased without maintaining the temperature in a temperature range equal to or higher than an A.sub.1 point of an Fe—C phase diagram and lower than the sintering temperature of the green compact, (II) a heating rate is set to 12° C./s or more in a temperature range of the A.sub.1 point to an A.sub.3 point of the Fe—C phase diagram, and (III) a heating rate is set to 4° C./s or more in a temperature range of the A.sub.3 point of the Fe—C phase diagram to the sintering temperature of the green compact.

An aspect of the present disclosure provides an amorphous metal porous body that is a metal porous body including pores, the amorphous metal porous body including: powder particle connection bodies in which at least portions of amorphous alloy powder particles adjacent to each other are connected in a network structure; and a plurality of pores provided between the powder particle connection bodies.

An aspect of the present disclosure provides an amorphous metal porous body that is a metal porous body including pores, the amorphous metal porous body including: powder particle connection bodies in which at least portions of amorphous alloy powder particles adjacent to each other are connected in a network structure; and a plurality of pores provided between the powder particle connection bodies.

Provided is a brazing filler material for bonding iron-based sintered member that includes a sintered compact containing Cu, Mn, and a remainder of Ni and unavoidable impurities, and an oxide film formed on a surface of the sintered compact. An oxygen concentration may account for not less than 0.1% by mass of a total amount of the brazing filler material. The oxide film may contain Mn.

In the porous substrate loaded with porous nano-particles structure and one-step micro-plasma production method thereof, since the micro-plasma system enhances the electron density and promotes reaction speed in the reaction without generating thermal effect, the method may be performed at an atmosphere environment. The nano-particles also can be quickly obtained by aforementioned micro-plasma system. The electromagnetic field generated by the micro-plasma can drive the nano-particles to be loaded onto the porous substrate in a one step, rapid and low cost process to improve the conventional techniques which require a relatively long procedure time and a complicated process.

Provided is an iron-based soft magnetic powder for dust cores that enables production of a dust core having high density and low iron loss. An iron-based soft magnetic powder for dust cores comprises: an iron-based soft magnetic powder; a condensed aluminum phosphate layer on particle surfaces of the iron-based soft magnetic powder; and a silicone resin layer on a surface of the condensed aluminum phosphate layer, wherein the condensed aluminum phosphate layer is a continuous coating, and a total mass of the condensed aluminum phosphate layer and the silicone resin layer is 0.60 mass % or less with respect to 100 mass % of a total mass of the iron-based soft magnetic powder, the condensed aluminum phosphate layer, and the silicone resin layer.

Provided is an iron-based soft magnetic powder for dust cores that enables production of a dust core having high density and low iron loss. An iron-based soft magnetic powder for dust cores comprises: an iron-based soft magnetic powder; a condensed aluminum phosphate layer on particle surfaces of the iron-based soft magnetic powder; and a silicone resin layer on a surface of the condensed aluminum phosphate layer, wherein the condensed aluminum phosphate layer is a continuous coating, and a total mass of the condensed aluminum phosphate layer and the silicone resin layer is 0.60 mass % or less with respect to 100 mass % of a total mass of the iron-based soft magnetic powder, the condensed aluminum phosphate layer, and the silicone resin layer.