Kawasaki Steel Corporation

Jfe Steel Corporation

Other

Jfe Precision Corporation

Unisia Jecs Corporation

Kawasaki Steel Corporaton

Hitachi, Ltd.

Satoshi Uenosono

Shigeru Unami

Yukiko Ozaki

Kuniaki Ogura

Masashi Fujinaga

Naomichi Nakamura

Takashi Yoshimura

Mitsumasa Iijima

Yasuo Hatai

Takayuki Matsumoto

Hiroshi Sugihara

Hoshiaki Terao

Akio Sonobe

Hideaki Kobiki

Shin Koizumi

Hiroyuki Amma

Hiroyuki Anma

Takeo Kobayashi

Hiroki Ota

Hiroki Nakamaru

Toshio Nagase

Hiroyuki Ishikawa

Junichi Ohta

Yukiko Nakamura

Shingo Saito

Shigeaki Takajo

Ji-bin Yang

Jibin Yang

In a Cr&#x2014;Cu alloy that is formed by powder metallurgy and contains a Cu matrix and flattened Cr phases, the Cr content in the Cr&#x2014;Cu alloy is more than 30% to 80% or less by mass, and the average aspect ratio of the flattened Cr phases is more than 1.0 and less than 100. The Cr&#x2014;Cu alloy has a small thermal expansion coefficient in in-plane directions, a high thermal conductivity, and excellent processibility. A method for producing the Cr&#x2014;Cu alloy is also provided. A heat-release plate for semiconductors and a heat-release component for semiconductors, each utilizing the Cr&#x2014;Cu alloy, are also provided.

Cr-Cu alloy, method for producing the same, heat-release plate for semiconductor, and heat-release component for semiconductor

It is an object to provide an inexpensive alloy for heat dissipation having a small thermal expansion coefficient as known composite materials, a large thermal conductivity as pure copper, and excellent machinability and a method for manufacturing the alloy. In particular, since various shapes are required of the alloy for heat dissipation, a manufacturing method by using a powder metallurgy method capable of supplying alloys for heat dissipation, the manufacturing costs of which are low and which take on various shapes, is provided besides the known melting method. The alloy according to the present invention is a Cu&#x2014;Cr alloy, which is composed of 0.3 percent by mass or more, and 80 percent by mass or less of Cr and the remainder of Cu and incidental impurities and which has a structure in which particulate Cr phases having a major axis of 100 nm or less and an aspect ratio of less than 10 are precipitated at a density of 20 particles/&#x3bc;min a Cu matrix except Cr phases of more than 100 nm.

Alloy for heat dissipation of semiconductor device and semiconductor module, and method of manufacturing alloy

Mo of 0.05 to 1.0% by mass is adhered to the surfaces of an iron-based powder containing Mn of 0.5% by mass or less and Mo of 0.2 to 1.5% by mass as prealloyed elements by diffusion bonding, whereby an alloy steel powder is formed. Furthermore, a Ni powder of 0.2 to 5% by mass and/or a Cu powder of 0.2 to 3% by mass are added to the alloy steel powder, whereby a mixed powder for powder metallurgy is formed. The mixed powder for powder metallurgy according to the present invention enables production of sintered bodies having high density as well as superior tensile strength and rotating bending fatigue strength.

Mixed powder for powder metallurgy

An alloy steel powder for powder metallurgy includes an iron-based powder containing about 0.5 mass percent or less of Mn as a prealloyed element and 0.2 to about 1.5 mass percent of Mo as a prealloyed element; and a Mo-containing alloy powder bonded on the surface of the iron-based powder by diffusion bonding. In the alloy steel powder for powder metallurgy, a Mo average content [Mo](mass percent) satisfies formula 0.8&#x2267;[Mo]&#x2212;[Mo]&#x2267;0.05, wherein the content [Mo]is the above prealloyed Mo content (mass percent) in the iron-based powder.

Alloy steel powder for powder metallurgy

An iron-based mixed powder for powder metallurgy having improved machinability, without degrading the mechanical property of a sintered body made by compacting the iron-based mixed power. The iron-based mixed powder comprises a mixture of an iron-based powder, a powder for an alloy, a powder for machinability improvement, and a lubricant. The powder for machinability improvement comprises a manganese sulfide powder, and at least one selected from the group consisting of a calcium phosphate powder and a hydroxy apatite powder. Alternatively the powder for machinability improvement has an average particle diameter of 1 to 60 micrometers and comprise manganese sulfide powder and calcium fluoride powder.

Iron-based mixed powder for powder metallurgy and sintered body

A method for manufacturing sponge iron includes heating iron oxide together with a solid reducing agent to reduce the iron oxide into sponge iron, wherein the iron oxide includes a mixture of powdered hematite and powdered iron ore or a mixture of powdered hematite and powdered mill scale, the powdered hematite has a specific surface area of 2.0 m/g or more, and the content of the powdered hematite is 5-45% by mass with respect to the total quantity of iron oxide.

Method for producing sponge iron, and reduced iron powder and method for production thereof

In a preliminary molding step, a metallic powder mixtureobtained by blending an iron-based metal powderwith graphitesuch that the graphite is present in an amount of preferably not less than 0.1% by weight, more preferably not less than 0.3% by weight, is compacted into a preformhaving a density of not less than 7.3 g/cm. In a provisional sintering step, the preformis provisionally sintered at a predetermined temperature to form a metallic powder-molded bodyhaving a structure in which the graphite remains along a grain boundary of the metal powder. In a re-compaction step, the metallic powder-molded bodyis re-compacted into a re-compacted body. In a re-sintering step, the re-compacted bodyis re-sintered to obtain a sintered body. In a heat treatment step, the sintered bodyis heat-treated to obtain a heat-treated sintered body Accordingly, in accordance with the present invention, there are provided a re-compacted body produced from a metallic powder-molded body having an excellent deformability which is suitably applied to the production of machine parts exhibiting high mechanical properties due to the use of sintered metal, and a sintered body produced from the re-compacted body as well as a process for the production thereof.

Metallic powder-molded body, re-compacted body of the molded body, sintered body produced from the re-compacted body, and processes for production thereof

A manufacturing method for high-density iron-based powder compacts is disclosed. The temperature of the die is adjusted at ordinary temperature or at a predetermined temperature by preheating. A lubricant for die lubrication prepared by mixing at least two different lubricants having melting points higher than a predetermined temperature of the compaction pressure is sprayed at the upper part of the die and is introduced into the die and adhered by electrification to the surface of the die. The resulting die is filled with an iron-based mixed powder including a lubricant and molding is performed at ordinary temperature or at a temperature raised by heating. The at least two different lubricants having melting points higher than the predetermined temperature of the compaction pressure are preferably at least two materials selected from at least one of the following groups: metallic soaps, amide-based waxes, polyamides, polyethylenes, polypropylenes, polymers comprised of acrylic acid esters, polymers having methacrylic acid ester, plastics including fluorine and lubricants having layered crystal structures.

Lubricants for die lubrication and manufacturing method for high density iron-based powder compacts

The surface of the body of powder additive for use in powder metallurgy is coated with an organic binder, thereby obtaining powder additive to cause adhesion of the powder additive to the surface of iron-based powder by the organic binder, thereby providing a powder additive with no segregation of components and excellent flowability and compression, and an iron-based powder mixture manufactured by mixing the powder additive and the iron-based powder.

Powder additive for powder metallurgy, iron-based powder mixture for powder metallurgy, and method for manufacturing the same

A magnetite-iron based composite powder includes magnetite with a ratio of X-ray diffraction intensity to that of &agr;-Fe of about 0.001 to about 50 and has an average primary particle size of about 0.1 to about 10 &mgr;m. The composite powder can highly dehalogenate organic halogen compounds and exhibits satisfactory absorption power of high frequency electromagnetic waves after molding. An ultrafine nonferrous inorganic compound powder may adhere to the surface of the composite powder, or at least the composite powder may adhere to the surfaces of small particles of a nonferrous inorganic compound to thereby yield a composite powder composition. The composite powder can be produced by partial reduction of a material powder containing a hematite based powder or by complete reduction and subsequent partial oxidation of the material powder.

Magnetite-iron based composite powder, magnetite-iron based powder mixture, method for producing the same, method for remedying polluted soil, water or gases and electromagnetic wave absorber

A Mo source powder is added to and mixed with an iron-based powder containing 1.0% by mass or less of prealloyed Mn to yield a powder mixture containing 0.2 to 10.0% by mass of Mo, the resulting powder mixture is subjected to heat treatment in a reducing atmosphere to thereby yield an alloyed steel powder containing Mo as a powder partially diffused and bonded to a surface of the iron-based powder particles. The prepared alloyed steel powder for powder metallurgy has satisfactory compactability. The use of this alloyed steel powder can produce a sintered powder metal body (an intermediate material after compaction and preliminary sintering in re-compaction of sintered powder materials process) for highly strong sintered member.

Alloyed steel powder for powder metallurgy

A sintered iron-based powder metal body with lower re-compacting load and having a high density and a method of manufacturing an iron-based sintered component with fewer pores of a sharp shape and having high strength and high density.

Iron-based sintered powder metal body, manufacturing method thereof and manufacturing method of iron-based sintered component with high strength and high density

On the basis of mass percentage of a mixture, 1-5% of Ni powder, 0.5-3% of Cu powder, and 0.2-0.9% of graphite powder are mixed into an alloy steel powder containing 0.5-3 mass % of prealloyed Ni, more than 0.7 to 4 mass % of prealloyed Mo, and the balance being Fe and unavoidable impurities. The alloy steel powder may contain 0.2-0.7 mass % of prealloyed Cu in addition to Ni and Mo.

Iron based mixed power high strength sintered parts

In order to improve machinability of a sintered compact, a phosphate compound of an alkali earth metal (calcium phosphate compound or the like) is mixed with an iron-based powder, or an alkali earth metal fluoride (calcium fluoride, or the like) is further mixed with the iron-based powder. Alternatively, the alkali earth metal fluoride, together with a graphite powder, is preferably fixed to recesses of the iron-based powder.

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Chiba, Japan

Satoshi Uenosono