Sliding member

A sliding member for a journal bearing, the sliding member comprising a back-metal layer and a sliding layer on the back-metal layer,

• wherein the sliding member has a partial cylindrical shape,
• wherein the sliding layer comprises a synthetic resin and fibrous particles dispersed in the synthetic resin at a volume ratio of 10 to 35% of the sliding layer,
• wherein the sliding layer is composed of a sliding surface side region including a sliding surface of the sliding layer and an interface side region including an interface between the sliding layer and the back-metal layer, a thickness of the interface side region being 15 to 50% of a thickness of the sliding layer,
• wherein, in the sliding surface side region, the fibrous particles have a first average particle size Dsur, axi of 5 to 30 μm in view of an axial cross-section, and have a second average particle size Dsur, cir in view of a circumferential cross-section, the second average particle size Dsur, cir is 5 to 20% of the first average particle size Dsur, axi,
• wherein, in the interface side region, the fibrous particles have a third average particle size Dint, cir of 5 to 30 μm in view of a circumferential cross-section, and have a forth average particle size Dint, axi in view of an axial cross-section, the forth average particle size Dint, axi is 5 to 20% of the third average particle size Dint, cir.
• wherein, in the sliding surface side region in view of the axial cross-section, the fibrous particles therein includes fibrous particles having a length of a major axis of not shorter than 20 μm, a volume ratio of the fibrous particles having the major axis length of not shorter than 20 μm to a total volume of the fibrous particles in the sliding surface side region being not less than 10%, and a dispersion index of the fibrous particles having the major axis length of not shorter than 20 μm is not less than 5, and
• wherein, in the interface side region in view of the circumferential cross-section, the fibrous particles therein includes fibrous particles having a length of major axis of not shorter than 20 μm, a volume ratio of the fibrous particles having the major axis length of not shorter than 20 μm to a total volume of the fibrous particles in the interface side region being not less than 10%, and a dispersion index of the fibrous particles having the major axis length of not shorter than 20 μm is not less than 5,
• wherein the dispersion index is defined as an average of ratios X1/Y1 of the fibrous particles, where X1 represents a length of a fibrous particle in a cross-section in a direction parallel to the sliding surface, and Y1 represents a length of a fibrous particle in the cross-section in a direction perpendicular to the sliding surface.