Sliding member having a novel pore structure on the sliding surface thereof

Claim 2

A sliding member which has a hardness of at least HRc 50 and has micropores for determining the surface roughness of the sliding surface thereof, wherein said micropores, when measured with a particle counter, in an amount ranging from 5% to 40% based on an area of the sliding surface and ranging from 2,000 to 150,000 per mm 2 of the sliding surface have a diameter of at least 0.5 μm and further have a top portion of ridges which define said micropores and which have a high flatness in terms of the relative load curve, said relative load curve being defined by an accumulative percentage (t k ) and a cutting depth (CV k ) and said accumulative percentage (t k ) being defined by: ##EQU3## wherein L is the standard measuring length of the sliding member extending in a direction parallel to the sliding surface, k is a number not greater than a predetermined number of divided sections of the ridges which are divided by imaginary lines extending parallel to an average roughness line, the cutting depth (CV k ) is a distance between a top imaginary line which passes over a top of the highest ridge and a kth imaginary line which passes over one or more of the ridges, and l k is a total length of the ridges which are cut by the knth imaginary line corresponding to the cutting length CV k , said flatness in terms of the relative load curve being defined by both: an accumulative percentage (t k ) of 5% or less at a cutting depth (CV k ) of less than 1 μm and an accumulative percentage (t k ) of more than 5% but less than 40% at a cutting depth (CV k ) of less than 0.5 μm.

Claim 3

A sliding member according to claim 1, said sliding member being in slidable contact with and being displaced relative to an opposed member.

Claim 4

A sliding member according to claim 2, said sliding member and said opposed member being a shoe and a swash plate or a shoe-housing, respectively, of a swash plate-type compressor.

Claim 5

A sliding member according to claim 2, said sliding member and said opposed member being a sliding bearing and another member respectively, of an internal-combustion engine.

Claim 6

A sliding member according to claim 2, said sliding member and said opposed member being a vane and a rotor, respectively, of a rotary compressor.

Claim 7

A sliding member according to claim 2, said sliding member and said opposed member being a vane and a housing or side plate, respectively, of a rotary compressor.

Claim 8

A sliding member according to claim 2, said sliding member and said opposed member being a rotor and a housing, respectively, of a rotary compressor.

Claim 9

A sliding member according to claim 2, wherein the number of said micropores is from 10,000 to 100,000 per mm 2 .

Claim 10

A sliding member according to claim 1, said sliding member being either a stationary member or a movable member of a mechanical seal or both, said movable member being rotatably pressed against a surface portion of said stationary member and being secured to a rotating shaft which is rotated relative to said stationary member, which is rigidly secured to said mechanical seal.

Claim 11

A sliding member according to claim 9, wherein said cutting depth (CV k ) is 0.5 μm or less at the accumulative percentage (t k ) 80%.

Claim 12

A sliding member according to claim 9, wherein the number of said micropores is from 10,000 to 100,000 per mm 2 .

Claim 13

A sliding member according to claim 9, wherein the diameter of said micropores is 30 μm at the most.

Claim 14

A sliding member according to claim 9, said sliding member consisting of iron-based material.

Claim 15

A sliding member according to claim 13, wherein the diameter of said micropores is 100 μm at the most.

Claim 16

A sliding member according to claim 9, said sliding member consisting of ceramic material.

Claim 17

A sliding member according to claim 1, said sliding member consisting of iron-based material.

Claim 18

A sliding member according to claim 1, said sliding member consisting of ceramic material.

Claim 19

A sliding member according to claim 8, 9, or 17, wherein the diameter of said micropores is 500 μm at the most.

Claim 20

A sliding member produce by the steps of: preparing a sliding body which has a hardness of at least HRc 50 and has micropores for determining the surface roughness of the sliding surface thereof, wherein said micropores, when measured with a particle counter, are present essentially in an amount ranging from 5% to 40% based on an area of the sliding surface and range from 20,000 to 150,000 per mm 2 on the sliding surface and have a diameter of at least 0.5 μm; and slightly rounding a top portion of ridges which define said micropores, thereby providing a flat or round configuration in terms of the relative load curve, said relative load curve being defined by an accumulative percentage (t k ) and a cutting depth (CV k ) and said accumulative percentage (t k ) being defined by: ##EQU4## wherein L is the standard measuring length of the sliding member extending in a direction parallel to the sliding surface, k is a number not greater than a predetermined number of divided sections of the ridges which are divided by imaginary lines extending parallel to an average roughness line, the cutting depth (CV k ) is a distance between a top imaginary line which passes over the top of the highest ridge and the kth imaginary line which passes over one or more of the ridges, and l k is a total length of the ridges which are cut by the knth imaginary line corresponding to the cutting length CV k , said flatness in terms of said relative load curve being defined by both: an accumulative percentage (t k ) of 5% or less at a cutting depth (CV k ) of less than 1 μm and an accumulative percentage (t k ) of more than 5% but less than 40% at a cutting depth of less than 0.5 μm.

Claim 21

A sliding member produce by the steps of: preparing a sliding body which has a hardness of at least HRc 50 and has micropores for determining the surface roughness of the sliding surface thereof, wherein said micropores, when measured with a particle counter, are present essentially in an amount ranging from 5% to 40% based on an area of the sliding surface and range from 20,000 to 150,000 per mm 2 on the sliding surface and have a diameter of at least 0.5 μm; and slightly rounding a top portion of ridges which define said micropores, thereby providing a flat or round configuration in terms of the relative load curve, said relative load curve being defined by an accumulative percentage (t k ) and a cutting depth (CV k ) and said accumulative percentage (t k ) being defined by: ##EQU4## wherein L is the standard measuring length of the sliding member extending in a direction parallel to the sliding surface, k is a number not greater than a predetermined number of divided sections of the ridges which are divided by imaginary lines extending parallel to an average roughness line, the cutting depth (CV k ) is a distance between a top imaginary line which passes over the top of the highest ridge and the kth imaginary line which passes over one or more of the ridges, and l k is a total length of the ridges which are cut by the knth imaginary line corresponding to the cutting length CV k , said flatness in terms of said relative load curve being defined by both: an accumulative percentage (t k ) of 5% or less at a cutting depth (CV k ) of less than 1 μm and an accumulative percentage (t k ) of more than 5% but less than 40% at a cutting depth of less than 0.5 μm.