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 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 Ai 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.

The present disclosure relates to a shot used for blast processing, the shot being made of an iron-based alloy containing C: 0.20 to 0.50% by mass, Si: 0.50 to 1.10% by mass, and Mn: 0.50 to 1.15% by mass as additive elements, in which a mass ratio of C to Si is 0.30 to 0.75, a mass ratio of C to Mn is 0.30 to 0.75, and a mass ratio of Si to Mn is 0.70 to 1.60, and a Vickers hardness of the shot is HV 400 to 800.

A method for producing soft magnetic metal powder includes: a raw material powder preparing step of preparing metal raw material powder having metal raw material particles including iron, silicon, and boron; a mixture step of mixing the metal raw material powder and a carbon source substance and obtaining mixed powder; and a heat treatment step of performing heat treatment on the mixed powder in a non-oxidizing atmosphere containing nitrogen at a heat treatment temperature of 1,250 C. or higher and making the metal raw material particles spherical.

A method for producing soft magnetic metal powder includes: a raw material powder preparing step of preparing metal raw material powder having metal raw material particles including iron, silicon, and boron; a mixture step of mixing the metal raw material powder and a carbon source substance and obtaining mixed powder; and a heat treatment step of performing heat treatment on the mixed powder in a non-oxidizing atmosphere containing nitrogen at a heat treatment temperature of 1,250 C. or higher and making the metal raw material particles spherical.

In one aspect, methods of foil ling tooling articles from tool steel powder compositions via additive manufacturing techniques are described herein. A method of forming a tooling article comprises consolidating powder alloy into the tooling article via an additive manufacturing technique and heat treating the tooling article to provide the tooling article hardness of 35 to 65 HRC. The tooling article can be formed of an alloy composition comprising 0.2-2 weight percent carbon, 0-1 weight percent manganese, 0-1.5 weight percent silicon, 0-0.3 weight percent nickel, 0-15 weight percent cobalt, at least two of chromium, molybdenum, tungsten and vanadium in a combined amount of 5-25 weight percent and the balance iron. As described herein, the method can further comprise hot isostatic pressing the tooling article prior to the heating treatment.

Although high-manganese steels may have desirable mechanical strength and corrosion resistance, machining and casting can be difficult. Alternatively, high-manganese steel parts may be fabricated to near-net shape parts using powder metallurgical processing, such as hot pressing and powder injection molding, thereby significantly minimizing or eliminating the need for further machining of fabricated parts. Hot pressing processes may comprise: loading a container with a plurality of particulates comprising a high-manganese steel; establishing a reduced pressure state in the container after loading the container with the plurality of particulates, and sealing the container to maintain the reduced pressure state therein and to afford a sealed container; placing the sealed container in a pressure vessel; heating the pressure vessel at a predetermined temperature while applying a predetermined pressure isostatically to an exterior surface of the sealed container with a pressurizing gas to consolidate the plurality of particulates into a densified part having a near-net shape; and removing the sealed container to expose a surface of the densified part.

Disclosed herein are embodiments of soft magnetic alloy embodiments for use in additive manufacturing and structures fabricated from such alloys. In some embodiments, the fabricated structures comprise a continuous thin wall (or plurality thereof) having a geometry that promotes reduced eddy current losses and other performance enhancements. In some embodiments, the fabricated structures are used to make components, such as transformer cores and/or electric motors.

An iron powder with a small complex particle diameter is used for a molded body having a large real part of the complex relative permeability. A silane compound in an amount of from 0.1 to 0.3 in terms of Si/Fe ratio is added to a slurry containing a hydrated oxide of iron precipitate obtained through neutralization of an acidic aqueous solution containing a trivalent Fe ion with an alkali aqueous solution to coat the precipitate of the hydrated oxide of iron with a hydrolyzate of the silane compound, in which a phosphorus-containing ion in an amount of from 0.003 to 0.1 in terms of P/Fe ratio co-exists in the slurry. The hydrated oxide of iron precipitate after coating is recovered through solid-liquid separation, and then heated to provide iron particles coated with a silicon oxide. The silicon oxide coating is dissolved and removed to provide the iron powder.

An iron powder with a small complex particle diameter is used for a molded body having a large real part of the complex relative permeability. A silane compound in an amount of from 0.1 to 0.3 in terms of Si/Fe ratio is added to a slurry containing a hydrated oxide of iron precipitate obtained through neutralization of an acidic aqueous solution containing a trivalent Fe ion with an alkali aqueous solution to coat the precipitate of the hydrated oxide of iron with a hydrolyzate of the silane compound, in which a phosphorus-containing ion in an amount of from 0.003 to 0.1 in terms of P/Fe ratio co-exists in the slurry. The hydrated oxide of iron precipitate after coating is recovered through solid-liquid separation, and then heated to provide iron particles coated with a silicon oxide. The silicon oxide coating is dissolved and removed to provide the iron powder.

A system and method of forming a wear resistant composite material includes placing a porous wear resistant filler material in a mold cavity and infiltrating the filler material with a matrix material by heating to a temperature sufficient to melt the matrix material, then cooling the assembly to form a wear resistant composite material. The system and method can be used to form the wear resistant composite material on the surface of a substrate, such as a part for excavating equipment or other mechanical part. One suitable matrix material may be any of a variety of ductile iron alloys.