Taiho Kogyo Co., Ltd.

Denso Corporation

Hiromi Yokota

Daisuke Yoshitome

Ryo Mukai

Takashi Tomikawa

Hitoshi Wada

Kao Mouri

Nahomi Hamaguchi

Masashi Suzuki

Shinichi Kato

Masanori Akizuki

Youichi Murakami

Akira Sawamoto

Takao Masamura

Eichi Sato

Toshihiko Kira

Takahiro Nozu

Naruhiko Inayoshi

Hiroaki Hayakawa

Atsushi Koyama

Hiroaki Kobayashi

Hiroyuki Kawaguti

Youichiro Kitagawa

When a Cu&#x2014;Sn&#x2014;Bi had&#x2014;particle based sliding material is used for sliding, Cu of Cu matrix flows and covers up Bi phase. Seizure resistance lowers as time passes. A Pb-free sliding material preventing the reduction of seizure resistance is provided. (1) Composition: from 1 to 15% of Sn, from 1 to 15% of Bi, from 0.02 to 0.2% of P, and from 1 to 10% of hard particles having an average diameter of from 50 to 70 &#x3bc;m, with the balance being Cu and unavoidable impurities. (2) Structure: Bi phase and the hard particles are dispersed in the copper matrix, and all of said hard particles are bonded to the copper matrix.

Pb-free copper alloy sliding material

Seizure resistance and wear resistance of Cu&#x2014;Bi&#x2014;In copper-alloy sliding material are enhanced by forming a soft phase of as pure as possible Bi. Mixed powder of Cu&#x2014;In cuprous alloy powder and Cu&#x2014;Bi containing Cu-based alloy powder is used. A sintering condition is set such that Bi moves outside particles of said Cu&#x2014;Bi containing Cu-based powder and forms a Bi grain-boundary phase free of In, and In diffuses from said Cu&#x2014;In containing Cu-based powder to said Cu&#x2014;Bi containing Cu-based powder.

Process for production of sintered copper alloy sliding material and sintered copper alloy sliding material

A sliding material based on graphite-added resin containing 5 to 60% by weight of graphite particles having an average particle diameter of from 5 to 50 &#x3bc;m, and a degree of graphitization of 0.6 or more, with the balance being one or more of polyimide resin and polyamide-imide resin, and further, the number of the graphite particles having a minimum diameter/maximum diameter ratio (hereinafter referred to as 'particle ratio') of 0.5 or more amounts to 50% or more of the total number of the graphite particles observed in a photograph of an optional cross section of the sliding material based on graphite-added resin.

Sliding material based on graphite-added resin and sliding member

A method of producing a Pb-free copper-alloy sliding material containing 1.0 to 15.0% of Sn, 0.5 to 15.0% of Bi and 0.05 to 5.0% of Ag, and Ag and Bi from an Ag&#x2014;Bi eutectic. If necessary, at least one of 0.1 to 5.0% of Ni, 0.02 to 0.2% P, 0.5 to 30.0% of Zn, and 1.0 to 10.0 mass % of at least one of a group consisting of FeP, FeP, FeB, NiB and AlN may be added.

Pb-free copper-alloy sliding material, and plain bearing

Sliding parts are made of Pb-free Cu&#x2014;Bi based sintered material. The side in contact with a shaft is machined to a predetermined roughness. A number of Bi phases are present on the finished surface. Stable performance of Bi is to be exhibited. Machined sintered material covers a portion of the Bi phases. The ratio of the exposed surface area of the Bi phases is 0.5% or more relative to the area of the finished surface.

Sliding part made of Pb-free Cu-Bi based sintered alloy

The present invention relates to sliding material provided by sintering a lead-free copper or copper alloy and contains at least one mineral selected from the group consisting of talc, mica, kaolinite mineral and montmorillonite mineral. Pb has conventionally been included in sliding materials for the purpose of obtaining conformability and seizure resistance. Despite the absence of Pb, the Pb-free copper-based sliding material and sliding parts according to the present invention have improved sliding properties.

Lead-free copper-based sintered sliding material and sliding parts

In a Cu&#x2014;Bi based sintered alloy, to which hard particles, such as FeP, are added, the main constituent components of the microstructure are a Cu matrix, Bi phase and the hard particles. In the sintering method of the present invention, the flow of the Bi phase is suppressed to as low level as possible. The novel structure is that the contact between the Bi phase and hard particles is kept to a low ratio. A lead-free bearing used for a fuel injection pump according to the present invention contains from 1 to 30 mass % of Bi and from 0.1 to 10 mass % of hard particles having from 10 to 50 &#x3bc;m of the average particle diameter, the balance being Cu and unavoidable impurities. The properties of the main component phases are utilized at a high level such that the sliding properties are equivalent to those of a Pb containing Cu-based sintered alloy.

Pb-free bearing used for fuel-injection pump

In a Pb-free copper-based sintered alloy containing from 1 to 30% of Bi and from 0.1 to 10% of hard matter particles having from 10 to 50 &#x3bc;m of average particle diameter, the Bi phase has a smaller average particle diameter than that of the hard matter particles and is dispersed in the Cu matrix, or the hard matter particles having 50% or less of a contact length ratio with the Bi phase based on the total circumferential length of the hard particle, which are in contact with said Bi phase, are present in a ratio of 70% or more based on the entire number of the hard matter particles.

Pb-free copper-alloy sliding material

Copper-base sintered sliding material excellent in slipperiness and

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Aichi, Japan

Hiromi Yokota