Sliding member

Patent metadata

Field	Value
Publication number	US-10995296-B2
Application number	US-201715432439-A
Country	US
Kind code	B2
Filing date	Feb 14, 2017
Priority date	Feb 15, 2016
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

A sliding member includes a back metal layer and a sliding layer on the back metal layer. The sliding layer includes a synthetic resin matrix and graphite particles dispersed in the matrix in a volume ratio of 5-50% of that of the sliding layer. The graphite particles are composed of spheroidal and flake-like particles. The flake-like particles have a volume ratio of 10-40% of total graphite particles. The spheroidal particles have a cross-sectional structure with a plurality of AB planes of a graphite crystal laminated along a curved particle surface, from the surface toward a center direction. The flake-like graphite particles have a cross-sectional structure with the plurality of AB planes laminated in a thickness direction of the thin plate shape. The spheroidal particles have an average particle size of 3-50 μm, and the flake-like graphite particles have an average particle size of 1-25 μm.

First claim

The invention claimed is:

1. A sliding member comprising:
a back metal layer; and
a sliding layer on the back metal layer, the sliding layer comprising a synthetic resin matrix and graphite particles dispersed in the synthetic resin matrix, the graphite particles having a volume ratio of 5 to 50% of a volume of the sliding layer,
wherein the graphite particles include spheroidal graphite particles and flake-like graphite particles having a thin plate shape, the flake-like graphite particles having a volume ratio of 10 to 40% of a total volume of the graphite particles,
wherein the spheroidal graphite particles have a cross-sectional structure in which a plurality of AB planes of a graphite crystal are laminated along a curved particle surface, from the particle surface toward a center direction,
wherein the flake-like graphite particles have a cross-sectional structure in which the plurality of AB planes are laminated in a thickness direction of the thin plate shape,
wherein the spheroidal graphite particles have an average particle size of 3 to 50 μm, and the flake-like graphite particles have an average particle size of 1 to 25 μm,
wherein the spheroidal graphite particles have an average aspect ratio of 1.5 to 4.5,
wherein the flake-like graphite particles have an average aspect ratio of 5 to 10, and
wherein an anisotropic dispersion index of the flake-like graphite particles is not less than 3, the anisotropic dispersion index being defined as an average value of a ratio X1/Y1 of each of the flake-like graphite particles, where
X1 is defined as a length of each flake-like graphite particle in a direction parallel to a sliding surface when viewed in a cross-sectional structure perpendicular to the sliding surface of the sliding layer, and
Y1 is defined as a length of each flake-like graphite particle in a direction perpendicular to the sliding surface when viewed in the cross-sectional structure perpendicular to the sliding surface of the sliding layer.

2. The sliding member according to claim 1 , wherein the synthetic resin matrix is made of one or more synthetic resins selected from a group consisting of PAI, PI, PBI, PA, phenol, epoxy, POM, PEEK, PE, PPS and PEI.

3. The sliding member according to claim 1 , wherein the sliding layer further comprises 1 to 20 volume % of one or more solid lubricants selected from a group consisting of MoS 2 , WS 2 , h-BN and PTFE.

4. The sliding member according to claim 1 , wherein the sliding layer further comprises 1 to 10 volume % of one or more fillers selected from a group consisting of CaF 2 , CaCO 3 , talc, mica, mullite, iron oxide, calcium phosphate and Mo 2 C.

5. The sliding member according to claim 1 , further comprising a porous metal layer between the back metal layer and the sliding layer.

Assignees

• Daido Metal Co

Inventors

• Yamauchi Takayoshi

Classifications

• C10N2010/16

  Groups 8, 9, or 10 · CPC title

• F16C2208/02

  comprising fillers, fibres · CPC title

• C08K2003/265

  Calcium, strontium or barium carbonate · CPC title

• C10N2050/14

  Composite materials or sliding materials in which lubricants are integrally molded · CPC title

• C09D179/08

  Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors · CPC title