A sealed bearing assembly includes seal members each including a seal lip with multiple protrusions, and being arranged such that oil passages are defined between the seal lip and a seal sliding surface which is configured to slide circumferentially relative to the protrusions such that the oil passages communicate with a bearing internal space and an exterior of the bearing, and prevent passage of foreign objects having particle diameters larger than a predetermined value therethrough. The seal lip and the seal sliding surface are arranged such that, when the bearing rotates, lubricating oil in the oil passages is pulled into spaces between the seal lip and the seal sliding surface such that a fluid lubricating condition is created between the seal lip and the seal sliding surface, due to a wedge effect.

There is prepared a formed body constituted of steel and having an outer circumferential surface having an annular groove having a bottom surface to serve as a raceway surface of the bearing ring. In the step of forming a heated region, the formed body is induction heated to form a heated region including the bottom surface of the groove and heated to a temperature of at least an A.sub.1 point. In the cooling step, the whole of the heated region is simultaneously cooled to a temperature of not more than an M.sub.s point. The step of retaining the formed body in a state in which heating is stopped is performed after the step of forming a heated region before the step of cooling. In the step of retaining, dispersion in temperature in the heated region in the circumferential direction is suppressed to not more than 20 C.

A sliding member which has a hardness suitable for use under heavy-load conditions and which exhibits excellent abrasion resistance property. A sliding surface is formed on a surface of a sliding layer that slidably supports an object to be slid. The sliding surface is then shot-blasted and is formed to have an uneven shape exhibiting an arithmetic average roughness (Ra) of more than 0 to 2.0 m, a ten-point average roughness (Rz) of more than 0 to 7.5 m, and a surface hardness (Hv) of 150 to 250.

A sealed bearing assembly includes seal members each including a seal lip formed with multiple protrusions, and arranged such that oil passages are formed between the seal lip and a seal sliding surface which slides circumferentially relative to the protrusions such that the oil passages communicate with the bearing internal space and the exterior of the bearing, and prevent passage of foreign objects having particle diameters larger than a predetermined value therethrough. The seal lip and the seal sliding surface are arranged such that when the bearing rotates, lubricating oil in the oil passages are pulled into the spaces between the seal lip and the seal sliding surface such that fluid lubricating condition is created between the seal lip and the seal sliding surface, due to the wedge effect.

In order to reduce friction of a crank shaft during operation by a large amount with low complexity through structuring sliding bearing surfaces (1) of the crank shaft through controlled introduction of microscopically small indentations (27) it is proposed for the center bearings and the crank bearings to only structure highly loaded portions of the bearing surface in circumferential direction and also in axial direction since this is already difficult to achieve in view of the operating gap towards the tool that only has a size of a few m.

First, in a primary sintering step, a manufacturing system 1 for a sliding member 2 laminates and thereby forms a sintered alloy layer 4 on back metal 3. Subsequently, a large number of indents 5 are formed on a front surface of the sintered alloy layer 4 by an indent-forming mechanism 14. Next, the back metal 3 and sintered alloy layer 4 are rolled by a reduction roll 15 and a secondary sintering process is applied to the sintered alloy layer 4. Consequently, the sliding member 2 is manufactured with the large number of indents 5 provided on a front surface. Since the indents 5 are formed on the sintered alloy layer 4 after the primary sintering step, it is possible to inhibit work hardening from occurring in the indents 5 and surrounding areas.

The present invention relates to a method for producing bearing shells of plain bearings, in which the bearing shells are blasted with corundum particles on the bearing metal side, in order in this way to produce residual compressive stresses in the blasted side of the bearing shell. Furthermore, the present invention relates to a bearing shell produced using such a method.