Kobe Steel, Ltd.

Other

Kabushiki Kaisha Kobe Seiko Sho (kobe Steel, Ltd.)

Hitachi Powdered Metals Co., Ltd.

Nobuaki Akagi

Hiroyuki Mitani

Hirofumi Houjou

Chio Ishihara

Hirofumi Hojo

Eiichiro Yoshikawa

Yoshikazu Seki

Makoto Iwakiri

Yoshihiro Ito

Sohei Yamada

Mitsuhiro Sato

Masaaki Satoh

Shinya Kawai

Hironori Suzuki

Hiroshi Yaguchi

Takehiro Tsuchida

Masamichi Chiba

Takeshi Ohwaki

Tomotsuna Kamijo

Masaki Amano

Kasumi Yanagisawa

Masaaki Sato

Yuji Taniguchi

Hideaki Ushio

Tetsuya Sawayama

Yasukumi Mochimizo

Yasukuni Mochimizo

Russell T Scott

Michael E Lutheran

The present invention relates to a powder mixture for iron-based powder metallurgy which is obtained by mixing an iron-based powder and at least one kind of powders selected from the group consisting of a Ca&#x2014;Al&#x2014;Si-based composite oxide powder and a Ca&#x2014;Mg&#x2014;Si-based composite oxide powder, in which with a peak height of a main phase exhibiting the highest peak intensity by X-ray diffraction as 100, the composite oxide powder has a relative height of 40% or less, with respect to the main phase, of a peak height of a second phase having the second highest peak intensity.

Powder mixture for iron-based powder metallurgy, and method for manufacturing sintered compact using same

One aspect of the present invention is a lubricant to be incorporated into a powder metallurgical mixed powder containing an iron-based powder. The lubricant includes a flaky organic material having an average particle diameter of from 0.1 &#x3bc;m to less than 3 &#x3bc;m. Another aspect of the present invention is a powder metallurgical mixed powder which contains an iron-based powder and the lubricant. Yet another aspect of the present invention is a method for producing a sintered compact. The method includes the step of mixing materials to give a powder metallurgical mixed powder containing an iron-based powder and the lubricant. The powder metallurgical mixed powder is compacted using a die to give a powder compact. The powder compact is sintered to give a sintered compact.

Lubricant, mixed powder for powder metallurgy, and method for producing sintered body

An iron-based soft magnetic powder for dust core having a high magnetic flux density, maintaining high electric insulation even after annealing, and more excellent in the mechanical strength in which a coating film having a phosphate conversion coating film is formed on the surface thereof and the peak height for the absorption of hydroxyl groups formed at 3700 cmto 2500 cmis 0.04 or more being indicated by absorbance when the coating film is analyzed by infrared diffuse reflectance spectroscopy.

Iron-based soft magnetic powder for dust core, method for manufacturing the same, and dust core

The present invention provides a binder which has excellent effect on suppression of segregation or dust emission, while exhibiting excellent fluidity both at ordinary temperatures and at high temperatures. The present invention is a binder which is blended for use in a mixed powder for powder metallurgy, said mixed powder containing an iron-based powder and an auxiliary starting material powder. This binder is characterized by being composed of one or more polymers that are selected from among butene polymers having a melting point of from 50&#xb0; C. to 85&#xb0; C. (inclusive) and a heated melt fluidity at 190&#xb0; C. of from 2.0 g/10 minutes to 3.6 g/10 minutes (inclusive) and methacrylic acid polymers having a weight average molecular weight of 1,000,000 or less.

Binder for powder metallurgy, mixed powder for powder metallurgy, and sintered body

Provided is an iron-based soft magnetic powder for dust core having a less coercive force, which is obtained by specifying the amount of inclusions in the iron-based powder for dust core, and at the same time, capable of decreasing the coercive force of a dust core produced using the iron-based soft magnetic powder. The iron-based soft magnetic powder for dust core is characterized by that when the cross-section of the iron-based soft magnetic powder particle is observed with a scanning electron microscope, the number of inclusions having an equivalent circle diameter from 0.1 to 3 &#x3bc;m is 1&#xd7;10pieces/mmor less and the number of inclusions having an equivalent circle diameter exceeding 3 &#x3bc;m is 10 pieces/mmor less.

Iron-based soft magnetic powder for dust core, preparation process thereof, and dust core

An iron-based magnetic powder for dust cores has layers of phosphoric acid-based film and silicone resin film sequentially formed on the surface thereof. The phosphoric acid-based film contains at least one element selected from the group consisting of Co, Na, S, Si, and W. The iron-based powder effectively keeps insulation among iron powder particles, excels in mechanical strength even though the amount of insulating material is reduced due to achieve high-density forming, and exhibits good thermal stability necessary for electrical insulating properties even after high-temperature heat treatment.

Iron-based soft magnetic powder for dust core, method for production thereof, and dust core

The invention relates to an iron-based soft magnetic powder for a dust core, wherein a film comprising Fe and Co, a phosphoric acid-based chemical conversion film and a silicone resin film are formed in this order on the surface of an iron-based soft magnetic powder, and to a dust core obtained by molding the iron-based soft magnetic powder for a dust core. The invention also relates to an iron-based soft magnetic powder for a dust core formed by coating the surface of an iron-based soft magnetic powder with an insulating film, wherein the powder has a particle diameter of from 45 &#x3bc;m to 180 &#x3bc;m, the insulating film is composed of two layers in which a lower layer composed of a phosphoric acid-based chemical conversion film and an upper layer composed of a silicone resin film, and each of the films has a thickness of from 100 nm to 280 nm, and to a dust core obtained by molding the iron-based soft magnetic powder for a dust core.

Iron-based soft magnetic powder for dust core and dust core

The present invention relates to an iron-base powder for a powder core, wherein when cross-sections of at least 50 iron-base powders are observed and a crystal grain size distribution containing at least a maximum crystal grain size is determined by measuring a crystal grain size of each iron-base powder, 70% or more of the measured crystal grains are a crystal grain having a crystal grain size of 50 &#x3bc;m or more. According to the iron-base powder of the invention, a coercivity of the powder core can be made small and a hysteresis loss can be reduced.

Powder core and iron-base powder for powder core

Mixture for powder metallurgy product and method for producing the same

A method for compacting powders for powder metallurgy comprises packing powders for powder metallurgy formulated with a lubricant in a compacting die applied with a lubricant on inner wall surfaces thereof, and subjecting the powders to warm or hot compaction. The powders contain the lubricant in an amount up to 0.2 wt %, non-inclusive of 0%, based on the total of the powders and the lubricant.

Method for compaction of powders for powder metallurgy

A powder metallurgy product which is made from constituent including iron powder. The iron powder includes iron grains which contain machinability improving element in the iron grains. The machinability improving element is configured to improve machinability of the powder metallurgy product and has a pinning effect. An amount (Q) of the machinability improving element is adjusted such that an absolute value of a differential coefficient (dS/dQ) is at least a predetermined value, where (S) is a grain size of iron in the powder metallurgy product.

Powder metallurgy product and method for manufacturing the same

Growing community of inventors

Takasago, Japan

Nobuaki Akagi