Hitachi Powdered Metals Co., Ltd.

Nissan Motor Company Limited

Denso Corporation

Honda Giken Kogyo Kabushiki Kaisha

Other

Hitachi Koki Co., Ltd.

Mitsubishi Steel Mfg. Co., Ltd.

Kei Ishii

Kazuhiko Takahashi

Takashi Suzuki

Tadayuki Tsutsui

Akira Fujiki

Yoshimasa Aoki

Hideaki Kawata

Hideo Shikata

Jyun-ichi Yamada

Yutaka Mabuchi

Jun Sakai

Takashi Murata

Chio Ishihara

Akira Fujiwara

Koichiro Hayashi

Kazuo Asaka

Yoshihiro Tanimura

Kunio Maki

Isao Makino

Tsuyoshi Akao

Atsushi Ehira

Yukihiro Maekawa

Tamio Takada

Makoto Kano

Keitaro Suzuki

Katsuyuki Nakamura

Hiroyuki Endo

Tsutomu Saka

Yuuichi Aoki

Masaki Shimizu

Bo Hu

Yutaka Ikenoue

Masaki Toriumi

Sumihisa Kotani

Yoshihiro Maki

Yuji Soda

Ichiro Tanimoto

Tomoaki Arakawa

Kouji Yamada

Yukio Tokuyama

Sadayuki Abo

Yuuji Yamanishi

Osamu Murai

Ryoji Sato

Kouichi Aonuma

Seigo Sato

Yuji Yamanishi

Hiroyuki Endoh

Yukata Ikenoue

Jyun-Ichi Yamada

Disclosed is a sintered gear composed of a sintered alloy having a metal matrix and pores. The tooth surface () of the tooth and the bottom land () have a densified layer () in which the porosity is reduced to 10% or less from the sintered alloy. The densified layer at the tooth surface is formed with a thickness of 300 to 1,000 microns, and the densified layer at the bottom land is formed with a thickness of 10 to 300 microns. The boundary surface of the densified layer is continuous from the tooth surface side to the bottom land side so as not to have a substantial level difference.

Sintered gear

A sintered sprocket for a silent chain is obtained from a material with few addition elements by a simple densifying method. The sintered sprocket is made of an ferrous material having an ovarall composition containing Cu at 1 to 2%, C at 0.5 to 0.8%, Mn as an inevitable impurity at 0.10% or less, and balance of Fe and other inevitable impurities by mass and has a density of 7.1 Mg/mor higher, 65 HRA or higher as a hardness in the gear teeth, and a martensite, sorbite, bainite, or their mixed structure as a cross-sectional microscopic structure in at least the gear teeth and the peripheral area of the gear teeth.

Sintered sprocket for silent chain and production method therefor

The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 &#x3bc;m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss Wand hysteresis loss W, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.

Production method for powdered core

An inexpensive mechanical fuse having a high fatigue limit ratio and high rupture reliability, and superior in forming performance, and a method of manufacturing the same are presented. The mechanical fuse is composed of Fe-based sintered alloy, and comprises an inner rimfixed to one power transmission shaft, an outer rimfixed to the other power transmission shaft, and plural armsfor linking the inner rimand outer rim, which are formed integrally. The armsinclude rupture portionswhich are ruptured when exposed to an overload torque. By treating in steam, an iron oxide phase is formed in the surface layer and pore inner wall. The iron oxide phase is effective to form round pores and lower the notch sensitivity. As a result, the fatigue strength and fatigue limit ratio are enhanced.

Mechanical fuse and method of manufacturing the same

A mechanical fuse has further improved and stabilized fatigue limit ratio, and can obtain high reliability under a using condition in which cyclic loading is applied. The mechanical fuse includes a Fe-based sintered alloy that has at least one element of P at 0.15 to 1.5 mass %, Si at 0.4 to 2.0 mass %, and Mn at 1.0 to 4.0 mass %, and the remainder consisting of Fe and inevitable impurities. An iron oxide layer is formed on a pore inner wall and the pores have roundness of 0.004 or more. A method of production therefore is also provided.

Mechanical fuse and production method for the same

A sintered sprocket has a high overall density and excellent contact pressure resistance. The sprocket is produced from a sintered alloy selected from the following alloys ((1) to (3)), is densified to have a relative density of 95% or higher in the surface layer of the gear teeth by forming by rolling, having a surface hardness of 700 HV or higher, and is useful for a crankshaft, a cam shaft, a balancer shaft, or a water pump shaft of an internal combustion engine:

The invention relates to an iron-based high-temperature wear-resistant sintered alloy. This alloy contains 3.74-13.36 wt % W, 0.39-5.58 wt % V, 0.2-5.78 wt % Cr, 0.1-0.6 wt % Si, 0.39-1.99 wt % Mn, 0.21-1.18 wt % S, and up to 2.16 wt % C. This alloy includes 20-80 wt % of a first phase and 80-20 wt % of a second phase, each distributed therein, in the form of spots. The first phase contains 3-7 wt % W, up to 1 wt % Cr, 0.1-0.6 wt % Si, 0.2-1 wt % Mn, 0.1-0.6 wt % S, and up to 2.2 wt % C. The first phase may contain 0.5-1.5 wt % V, and in this case the vanadium content of the alloy becomes 0.79-5.88 wt %. The second phase contains 7-15 wt % W, 2-7 wt % V, 1-7 wt % Cr, 0.1-0.6 wt % Si, 0.2-1 wt % Mn, 0.1-0.6 wt % S, and up to 2.2 wt % of C. Each phase contains 0.3-1.6 wt % MnS and a carbide of at least tungsten, which are dispersed therein. The second phase further contains 10-20 areal % tungsten carbide (particle diameter: &gE;1 &mgr;m) dispersed therein. The alloy further contains 0.3-16 wt % MnS grains dispersed in grain boundaries and/or pores. The alloy is greatly improved in wear resistance, while suppressing damage to mating part in contact with the alloy.

High-temperature wear-resistant sintered alloy

Machinability is drastically improved while maintaining some degree of hardness in an Fe-based sintered alloy. A good machinability Fe-based sintered alloy has an overall composition of, in percent by weight, at least one element selected from the group consisting of P in an amount of 0.1 to 1.0% and Si in an amount of 2.0 to 3.0%, B in an amount of 0.003 to 0.31%, 0 in an amount of 0.007 to 0.69%, C in an amount of 0.1 to 2.0%, and the balance consisting of Fe and unavoidable impurities, has a matrix hardness ranging from Hv 150 to 250, and has free graphite dispersed therein.

Good machinability Fe-based sintered alloy and process of manufacture therefor

There is disclosed a method for manufacturing an Fe-based sintered alloy which is superb in machinability. This process comprises the steps of coating a paste-like coating agent including a compound of boron to a surface of a compact of Fe-based or Fe, Cu-based sintered alloy powder including carbon or a pre-sintered compact obtained by heating the compact at a diffusion temperature or less of carbon, and sintering a resultant compact or a pre-sintered compact at a diffusion temperature or more of carbon. An Fe-based sintered alloy manufactured through this process and a bearing cap made of such an Fe-based sintered alloy are also disclosed. In the invention, a film including a compound of boron and pyrolytic resin can be used instead of the paste-like coating agent.

Fe-based sintered alloy manufacturing process, Fe-based sintered alloy

The invention relates to a sintered alloy. This sintered alloy includes 3-13.4 wt % of W, 0.4-5.6 wt % or 0.8-5.9 wt % of V, 0.2-5.6 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, 0.6-2.2 wt % of C, and a balance of Fe. The sintered alloy includes first and second phase which are distributed therein, in a form of spots, respectively. The second phase is in an amount of from 20 to 80 wt %, based on the total weight of the first and second phases. The first phase contains 3-7 wt % of W, 0.5-1.5 wt % of optional V, up to 1 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. The second phase contains 3-15 wt % of W, 2-7 wt % of V, 1-7 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. When the manganese contents of the first and second phases and the total of the sintered alloy are respectively in a range of from 0.2 to 1.0 wt %, sulfur is respectively contained therein in an amount of from 0.1 to 0.6 wt %. The sintered alloy has wear-resistant at high temperature and good compatibility without damaging mating part that is in contact with the sintered alloy.

Disclosed is a sintered iron alloy, a method of manufacturing the same, a powdered mixture used for manufacturing the same and a method of modifying the surface of the iron alloy. The sintered iron alloy is produced by compacting a powdered mixture comprising: boron or boron compound which is selected from the group consisting of boron oxide, boron sulfide, boron halide, boron hydride, boric acid, borate and tetrafluoroborate; 0.1 to 2.0% by weight of graphite; and iron, and sintering it. Alternatively, the iron alloy is produced by impregnating a modifier containing boron or boron compound, into a green compact, a presintered compact or sintered body which contains iron and carbon, and heating it.

Manufacturing process of sintered iron alloy improved in machinability,

A source powder for a wear-resistant sintered material, consisting essentially of, in weight percentages, Cr: 3.0 to 6.0%, 2 Mo+W: 10.0 to 20.0%, V: 1.0 to 8.0%, Co: 10.0% or below, C: 0.20% to {0.01(2 Mo+W)+0.24 V}%, Si: 0.1 to 1.0%, Mn: 0.1 to 1.0% and the balance being Fe and unavoidable impurities, or one prepared by adding 0.10 to 0.8% of S to the above composition. This powder can be compacted into a green compact having a high green density, which can further give a wear-resistant sintered material having a high sintered density, hardness and strength.

Source powder for wear-resistant sintered material

The present invention relates to a method for producing, without quench-hardening process, a ferrous sintered alloy having satisfactory strength which is equal to that of the conventional ferrous sintered quenched material, and the method comprises the steps of: preparing a powder mixture by adding, in weight ratios, 1 to 2% of copper powder, 1 to 3% of Ni powder, and graphite to a ferrous alloy powder consisting of 3 to 5% of Ni, 0.4 to 0.7% of Mo, and the remainder Fe, the quantity of said graphite being determined such that the C-content after sintering is 0.2 to 0.7%; compacting said powder mixture in a tool to form a green compact; sintering said green compact in a non-oxidizing atmosphere at a temperature in the range of 1130.degree. to 1230.degree. C.; and cooling the sintered product in the sintering furnace at a rate of 5.degree. C./min. to 20.degree. C./min.

Method for producing ferrous sintered alloy having quenched structure

Disclosed is a sintered iron alloy and a method of manufacturing the same. The sintered alloy comprises: an alloy matrix and a lead phase for imparting lubricability to the sintered alloy. The alloy matrix comprises a first alloy phase being composed of 0.5 to 3% nickel by weight, 0.5 to 3% molybdenum by weight, 5.5 to 7.5% cobalt by weight, 0.6 to 1.2% carbon by weight, and the balance iron, and a second alloy phase being composed of 26 to 30% molybdenum by weight, 7 to 9% chromium by weight, 1.5 to 2.5% silicon by weight, and the balance cobalt. The content of the lead phase in the sintered alloy is not more than 3.5% by weight. The lead phase is dispersed in the alloy matrix and a pore which is formed in the alloy matrix. The ratio of the lead dispersed in the alloy matrix to the total lead phase is 60% by weight or more, and the lead phase dispersed in the alloy matrix is particles in which the maximum particle size is 10 .mu.m or less. In manufacture, a lead powder having a particle size of approximately 50 .mu.m or less is mixed a first raw material powder for the first alloy phase and a second raw material powder for the second alloy phase at a lead content of not more than 3.5% by weight. After compacting and sintering the mixture, the sintered compact is cooled so that the temperature of the compact in the vicinity of 328.degree. C. is cooled at a cooling rate of approximately 2.degree. C./min. or more.

Sintered iron alloy resistant to abrasion at high temperature and method

Growing community of inventors

Matsudo, Japan

Kei Ishii