Jfe Steel Corporation

Hyundai Motor Company

Kia Motors Corporation

Toshio Maetani

Akio Kobayashi

Naomichi Nakamura

Yukiko Ozaki

Yasuhiko Sakaguchi

Tomoshige Ono

Hak Soo Kim

Shigeru Unami

Tatsuhiko Hiratani

Takuya Takashita

Akira Fujita

Hiroharu Kato

Masashi Fujinaga

Akio Sonobe

Kohsuke Ashizuka

Hirofumi Enokido

Itsuya Sato

Hisashi Sudo

The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1):0.3&#xd7;Cu %+3&#xd7;Mo %&#x2264;2.7&#x2003;&#x2003;(1).

Iron-based prealloy powder, iron-based diffusion-bonded powder, and iron-based alloy powder for powder metallurgy using the same

Provided is an alloy steel powder for powder metallurgy containing an iron-based powder as a main component that is capable of achieving both high strength and high toughness in a sintered body using the same. In the alloy steel powder, the iron-based powder contains a reduced powder, and Mo content with respect to a total amount of the alloy steel powder is 0.2 mass % to 1.5 mass %, Cu powder content with respect to a total amount of the alloy steel powder is 0.5 mass % to 4.0 mass % and graphite powder content with respect to a total amount of the alloy steel powder is 0.1 mass % to 1.0 mass %.

Alloy steel powder for powder metallurgy and method of producing iron-based sintered body

An Fe&#x2014;Mo&#x2014;Cu&#x2014;C-based alloy steel powder for powder metallurgy has a chemical composition containing Mo: 0.2 mass % to 1.5 mass %, Cu: 0.5 mass % to 4.0 mass %, and C: 0.1 mass % to 1.0 mass %, with a balance being Fe and incidental impurities, wherein an iron-based powder has a mean particle size of 30 &#x3bc;m to 120 &#x3bc;m, and a Cu powder has a mean particle size of 25 &#x3bc;m or less. Despite the alloy steel powder for powder metallurgy having a chemical composition not containing Ni, a part produced by sintering a press formed part of the powder and further carburizing-quenching-tempering the sintered part has mechanical properties of at least as high tensile strength, toughness, and sintered density as a Ni-added part.

Alloy steel powder for powder metallurgy, and sintered body

A method for measuring an apparent density of a metal powder includes holding a metal powder in a vessel, applying an alternating magnetic flux to the metal powder using an exciting coil disposed outside the vessel, detecting the alternating magnetic flux passed through the metal powder using a search coil disposed outside the vessel, and determining an apparent density of the metal powder from an amplitude of the detected alternating magnetic flux using a calibration curve representing a correlation between the apparent density of the metal powder and the amplitude of an alternating magnetic flux prepared in advance. The method enables to measure the apparent density of a metal powder with a high precision in an on-line and non-contact manner without stopping a process of producing a mixed powder or a process of producing a powder compact.

Method and apparatus for measuring apparent density of metal powder, method and apparatus for producing mixed powder, and method and apparatus for producing powder compact

A finish heat treatment apparatus for an iron powder. Raw iron powder is placed on a continuous moving hearth and continuously charged into the apparatus. In a pretreatment zone, the raw iron powder is subjected to a pretreatment of heating the raw iron powder in an atmosphere of hydrogen gas and/or inert gas at 450 to 1100&#xb0; C. In decarburization, deoxidation, and denitrification zones, the pretreated iron powder is subsequently subjected to at least two treatments of decarburization, deoxidation, and denitrification. In the pretreatment zone, a hydrogen gas and/or an inert gas serving as a pretreatment ambient gas is introduced separately from an ambient gas used in the at least two treatments is introduced from the upstream side of the pretreatment zone and released from the downstream side so as to flow in the same direction as a moving direction of the moving hearth.

Finish heat treatment method and finish heat treatment apparatus for iron powder

In a finish heat treatment method and finish heat treatment apparatus for an iron powder, a raw iron powder is placed on a continuous moving hearth and continuously charged into the apparatus. In the pretreatment zone, the raw iron powder is subjected to a pretreatment of heating the raw iron powder in an atmosphere of hydrogen gas and/or inert gas at 450 to 1100&#xb0; C. In decarburization, deoxidation, and denitrification zones, the pretreated iron powder is subsequently subjected to at least two treatments of decarburization, deoxidation, and denitrification. In the pretreatment zone, a hydrogen gas and/or an inert gas serving as a pretreatment ambient gas is introduced separately from an ambient gas used in the at least two treatments is introduced from the upstream side of the pretreatment zone and released from the downstream side so as to flow in the same direction as a moving direction of the moving hearth.

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Tokyo, Japan

Toshio Maetani