Abstract: The invention relates to a metal-plastic plain-bearing composite material (2), in particular for producing plain bearing elements for lubricated applications, comprising a metal support layer (4), in particular of steel or bronze, and comprising a sliding layer (12) of a sliding material (8) of a matrix-forming PTFE polymer base with fillers that improve the tribological properties, said sliding layer being in sliding contact with a sliding partner, characterized in that the sliding material contains as fillers 1-15 vol % barium sulfate, 5-20 vol % aramid, 1-10 vol % polyimide and 1-15 vol % fluorothermoplastic, excluding PTFE, as well as a plain-bearing composite material and a plain bearing element.

Abstract: A leveling adjustment device attached to a machine tool with supporting foot portions being adjusted manually to change a height, which includes a sensing module and a microcontroller unit. The sensing module senses the machine tool for inclined extents in two directions perpendicular to each other and then generates a sensed data. The microcontroller unit receives the sensed data and provides a graphical operation interface with first blanks and second blanks. The first blanks are used to fill with a length and width data of the machine tool while the second blanks are used to fill with a coordinate data corresponding to each of the supporting foot portions. The microcontroller unit calculates an adjustment sequence and an adjustment value corresponding to each of the supporting foot portions based on the data in the first and second blanks in conjunction with the sensed data and then displays in the graphical operation interface.

Abstract: Embodiments of the invention relate to bearing apparatuses in which one bearing surface of the bearing apparatus includes diamond, while another bearing surface includes a non-diamond superhard material (e.g., silicon carbide). For example, a bearing apparatus may include a bearing stator assembly and a bearing rotor assembly. The bearing stator assembly and bearing rotor assembly each include a support ring and one or more superhard bearing elements generally opposed to one another. The bearing surface(s) of the rotor or stator may include diamond, while the bearing surface(s) of the other of the rotor or stator do not include diamond. Another bearing apparatus may include both thrust- and radial bearing components. The generally opposed thrust-bearing elements may include diamond, while the generally opposed radial bearing elements may not include diamond, but include a non-diamond superhard material, such as silicon carbide.

Abstract: A pressure applying system using a modular vise having a fixed base and an adjustable pusher assembly. The modular vise utilizes a bi-directional worm screw to apply a linear force from the pusher assembly to the working member relative to the fixed base. The fixed base is secured and located from below a bottom surface of the fixed base.

Abstract: A steam wand assembly for an espresso machine has features for preventing overheating of the tip of the steam wand. In a first aspect there is provided a steam wand device comprising a metallic main body tube, a steam hose that passes through the tube, the steam hose also passing through a flexible spacer that is within the tube. In a further aspect there is provided a steam wand device comprising a main body tube having a metallic primary tube and a metallic tip, the primary tube and the tip being attached to one another by a polymeric steam nozzle, the nozzle having a central bore that extends from an inlet adjacent to a lower end of a steam hose to an exit opening.

Abstract: A dynamic line guiding system for high speeds and/or long displacement paths, with an energy chain arranged as lying on the side, which chain, in the configuration of a first strand, a second strand, as well as a deflection curve, is displaceable back and forth. The energy chain is guided in a guide trough with two laterally-opposite side walls and a trough floor therebetween, wherein each strand is respectively displaceable with a lateral surface on a respective bearing surface on the trough floor, and is held, relative to the outside, by means of one of the two side walls. It is provided that the trough floor comprises at least one bearing surface with a step or a ramp, which counteracts a deviation of the first strand out of its intended target location on the respective bearing surface.

Abstract: A slider unit for a roof system of a motor vehicle has a slide body and a mounting unit which has a recess in which the slide body is accommodated. The slide body is mounted in the mounting unit such that, relative to the mounting unit, the slide body is movable in at least two directions in each case limited to a predefined distance and/or is pivotable about two axes limited to a predefined angle.

Abstract: A toothed shaft can be installed in a hollow shaft that has an internal toothing such that the toothed shaft is coupled in a positively locking fashion so as to be telescopic in a direction of a longitudinal axis. The toothed shaft may include a toothing region with teeth on an outer circumference and extending in an axial direction. In the toothing region a shaft core may be overmolded by way of an injection molding process with a sliding coating comprised of thermoplastic material. The sliding coating may have at least three impressions, with each of the at least three impressions featuring an aperture that extends through the sliding coating to a surface of the shaft core.

Abstract: An apparatus having a first sliding member having an outer wall surface and an inner wall surface defining a central opening. A second sliding member having an outer wall surface and that is configured for sliding insertion into the central opening of the first sliding member. A space is formed between first and second sliding members. The first sliding member slides and may be fixed at a selected location along the length of the second sliding member. The apparatus includes a slider insert having a center section and a pair of lips that engage the first sliding member for removably mounting the slider insert to the first sliding member such that the slider insert is located in the space between the first sliding member and the second sliding member. The slider insert slides with the first sliding member and prevents the first and second sliding members from contacting on another.

Abstract: A feed beam, a rock drilling unit and to a method of manufacturing a feed beam is provided. The feed beam includes a basic profile element, which has two or more superimposed material layers. At least one of the material layers may be made of a composite material.

Abstract: A resin coating layer has a shape line that indicates the shape of a surface and is divided by virtual straight lines parallel to the X axis and setting an area of recessed sections that protrudes below the virtual straight lines and an area of protruding sections that protrudes above the virtual straight lines. A virtual straight line at a position at which the area totals for the area of recessed sections and the area of protruding sections are equal is defined as the average line for unevenness. Areas that protrude downwards from this average line for unevenness are defined as recessed sections and areas that protrude above this average line for unevenness are defined as protruding sections. The average area Sa for one recessed section is 4-120 ?m2 and the number M of recessed sections between two points having a distance of 1 mm therebetween is 3-20.

Abstract: A rotor assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a rotor that has a hub carrying one or more rotatable blades. The rotor is mechanically attached to a shaft, and an annular seal is carried by the shaft. The annular seal includes a substrate and a first layer disposed on the substrate. The first layer includes copper, and a second layer is disposed on the first layer and arranged to establish a sealing relationship with the rotor. The second layer includes a solid lubricant. A method of sealing is also disclosed.

Abstract: A slide includes a carriage, a guide, and interposed pads allowing the carriage to be moved in translation in a longitudinal direction by relative sliding of the pads on contact surfaces distributed symmetrically on both sides of two planes: a horizontal plane parallel to the longitudinal direction and the transverse direction and a median plane parallel to the longitudinal direction and the vertical direction. The contact surfaces are oriented so as to form with the horizontal plane an angle between 30° and 70° inclusive.

Abstract: A window lifter assembly includes a guide rail defining an adjustment direction for a window pane, a cable for transmitting an adjusting force for moving the window pane along the guide rail, a driver element connected to the window pane and the cable, and a sliding element being a separate component from the driver element, wherein the driver element and the sliding element are connected via an at least two-stage latching connection, via which the sliding element and the driver element can be first connected to each other in a mounting position, wherein when the sliding element is shifted along the guide rail to an end position, moves relative of the sliding element the driver element such that the sliding element and the driver element move into a functional position which is different from the mounting position.

Abstract: In one aspect, the present disclosure provides a wearpad for a telescopic boom assembly including a first surface for contacting an outer boom of the boom assembly, a second surface for contacting an inner boom of the boom assembly, and a length, where the first surface and the second surface extend along the length, and where the length extends along a longitudinal direction. A chamfered portion of the wearpad may have a first end at a first location along the length and a second end at a second location along the length. The first surface and the second surface may converge along the chamfered portion. Thus, a first distance between the first surface and the second surface at the first end of the chamfered portion may be greater than a second distance between the first surface and the second surface at the second end of the chamfered portion.

Abstract: A slide-bearing assembly capable of enabling sliding of a load-carrying surface relative to a load-supporting structure, such that the slide-bearing assembly may include a first arrangement of at least one substantially nonmetallic elongate bearing element capable of extending along a first load-carrying surface and a second arrangement of at least two substantially nonmetallic elongate bearing elements capable of extending longitudinally in series along a second load-carrying surface parallel to the first load-carrying surface such that the second load-carrying surface is in non-coextensive supportive relationship with the first load-carrying surface.

Abstract: Durability-enhanced bearing assemblies, apparatuses, and motor assemblies using the same are disclosed. In an embodiment, a bearing assembly may include a plurality of superhard bearing elements distributed circumferentially about an axis. Each of the superhard bearing elements includes a bearing surface. The bearing assembly may further include a support ring structure that carries the plurality of superhard bearing elements. The support ring structure may have a first portion that exhibits a first yield strength and a second portion that exhibits a second yield strength. The first yield strength of the first portion may be greater than the second yield strength of the second portion.

Abstract: Downhole tools for use in downhole operations and electrical submersible pumping systems having an additively manufactured first part including a first layer having a first predetermined material property and a second layer having a second predetermined material property, wherein the first and second layers are layers of an integral piece and the first predetermined material property is different from the second predetermined material property and a second part configured to rotationally engage with the additively manufactured first part. One of the first part and the second part is rotated relative to the other of the first part and the second part in operation.

Abstract: There is provided a technique which can realize both of conformability and fatigue resistance. A sliding member and a slide bearing include a base layer and a coating layer provided on the base layer and having a sliding surface on which a counter material slides, and are characterized in that the coating layer is formed of a soft material which is softer than that for the base layer; and that, in the sliding surface, crystal grains of the soft material having an average grain diameter of 0.1 ?m or more and 1 ?m or less are aggregated into lumps, thereby forming aggregates having an average diameter of 3 ?m or more and 30 ?m or less.

Abstract: A wear pad assembly for a telescopic boom includes a wear pad having a first side for contacting an outer wall of an inner section of the boom, and a second side facing an inner wall of an outer section of the boom. At least one rigid plate is secured to the second side of the wear pad, and a stud in screw-threaded engagement with the outer section of the boom or a plate secured to the outer section of the boom is associated with each rigid plate, the end of stud and the associated rigid plate having mating formations to enable the stud to urge the first surface of the wear pad against the outer wall of the inner section while preventing the wear pad from being displaced in a plane normal to the axis of rotation of the stud.

Abstract: A steering device includes: a rack; a pinion; a pinion shaft having the pinion on an outer circumferential surface thereof; a rack shaft having the rack that engages with the pinion; a rack guide that is provided on a side of the rack shaft opposite from the pinion shaft and guides the rack shaft along an axis of the rack shaft; a biasing member that biases the rack guide against the rack shaft to press the rack against the pinion; a guide housing that accommodates the rack guide and the biasing member; and a buffer member provided between an outer circumferential surface of the rack guide and an inner circumferential surface of the guide housing. The buffer member has a cylindrical member and an elastic member. The elastic member is disposed on at least either one of an inner circumferential surface and an outer circumferential surface of the cylindrical member.

Abstract: A shoe 5 includes a spherical portion 5A in sliding contact with a sliding surface 4a that is a hemispherical concave portion of a piston 4, an end surface portion 5B in sliding contact with a swash plate 3, and a circular cylindrical portion 5C formed between the spherical portion 5A and the end surface portion 5B. Linear oil grooves 5F are formed in the outer peripheral surface of the cylindrical portion 5C.

Abstract: A telescopic shaft includes a male shaft having an outer circumference on which a plurality of protruding teeth are formed, and a female shaft having an inner circumference on which a plurality of tooth grooves are formed. The tooth grooves of the female shaft are fitted onto the protruding teeth of the male shaft such that the male shaft and the female shaft are relatively slidable in an axial direction and such that a rotational torque is transmittable between the male shaft and the female shaft. One of a curvature radius of a tooth surface of the protruding teeth and a curvature radius of a tooth surface of the tooth grooves is smaller than the other of the curvature radius of the tooth surface of the protruding teeth and the curvature radius of the tooth surface of the tooth grooves.

Abstract: A rotary shaft and method for reducing non-uniform heating thereof are provided. The rotary shaft may include a tubular body having a longitudinal axis extending therethrough. An outer surface of the tubular body may define a groove at least partially extending radially inward from the outer radial surface toward the longitudinal axis of the tubular body to define a depth thereof. The rotary shaft may include a thermal barrier at least partially disposed in the groove and configured to absorb at least a portion of heat generated from rotation thereof.

Abstract: Guide arrangement serving to guide a linear movement of a movable part (2) extending opposite a stationary part (1) along the movement axis and along a transverse direction oriented at a right angle to the movement axis, wherein the guide arrangement includes a support area belonging to the stationary part on which the movable part is slidingly supported and a roller guide arrangement (12) with a roller-guiding area belonging to the stationary part.

Abstract: A method of preventing wear in a blowout preventer includes the steps of forming an inner surface of a blowout preventer body to receive wear inserts at least one wear point in the blowout preventer body; and securing at least one wear insert on the formed inner surface of the blowout preventer body.

Abstract: A slide plate hinge comprises a fixed plate, and a slide plate. A slide plate sliding guide groove is respectively arranged on each of both sides of the fixed plate. The central section of the groove wall at one side of the sliding guide groove is of an elastic structure, and the elastic structure and the groove wall at the other side of the sliding guide groove clamps the slide plate. The slide plate hinge can implement the sliding guide and friction clamping on the slide plate by use of the sliding guide groove of an elastic structure, with high structural integration and concealability, thereby enabling the slide plate hinge to still have good hand feeling even without driving springs and enabling the slide plate to be stopped at any time amid the sliding process. The driving springs are not indispensable, so the thickness of the hinge can be reduced.

Abstract: A system for delivering a downhole tubular from a rack at an oilfield surface to a rig floor thereat. The system includes a trough for accommodating the tubular that is slidably engaged with a lift frame in a sledded fashion. Thus, for delivery of the tubular, the trough may be sleddingly extended from the lift frame. That is, as opposed to a roller type of coupling between the trough and tubular, a sledded coupling is utilized that may require comparatively less maintenance and mobilization time. This may be particularly the case where lighter weight tubulars of less than about 1,000 lbs., preferably under about 500 lbs., are being delivered.

Abstract: To provide a sliding member which has hardness that is suitable for the circumstance, to which heavy load is applied, and which is excellent in abrasion resistance property. The sliding member contains a sliding layer for slidably supporting a body to be slid, shot blasting being performed on a surface of the sliding layer, and a sliding surface formed on a surface of the sliding layer, the sliding surface having an uneven configuration with arithmetic mean roughness (Ra) of 1.0 ?m through 2.5 ?m, 10-point average roughness (Rz) of 5.0 ?m through 10.0 ?m, and surface hardness (Hv) of 220 through 250.

Abstract: In sliding members that slide against each other, a sliding portion of one sliding member is formed from amorphous carbon, and a sliding portion of another sliding member is formed from a copper alloy or an aluminum alloy.

Abstract: A swash plate 3 includes a substrate 11 made of an iron-based material, a hard first resin layer 12 provided to coat an end surface of the substrate 11, and a soft second resin layer 13 provided to coat the first resin layer 12. A spiral annular groove 12A is formed in a surface of the first resin layer 12, and the second resin layer 13 is provided to match the sectional shape of the first resin layer 12. With the soft second resin layer 13 on a sliding surface 3A of the swash plate 3, a swash plate 3 having a good fit in an initial stage of sliding can be provided. When the second resin layer 13 partially wears, a protrusion 12 of the first resin layer 12 of the hard resin is exposed to provide good wear resistance and good sliding properties.

Abstract: A sliding member is integrally formed of fluororesin as a whole, and a sliding surface to be slid with a slid member is made hydrophilic. A manufacturing method includes a step of exposing the sliding surface 2 of the sliding member 1 to water plasma 7 generated by Ar gas and vaporized water as raw materials and making the sliding surface 2 hydrophilic.

Abstract: A telescopic side arm for a refuse vehicle has an inner and outer boom. A mounting assembly secures the outer boom with a refuse vehicle. A plurality of bearing pads is positioned between the inner and outer booms to provide smooth movement between the inner and outer booms. A plurality of shims is associated with the bearing pads to assure a tight fit between the inner and outer booms.

Abstract: A boom assembly includes a first boom member and a second boom member slidable relative to the first member in a first direction. A stop member that at least partially defines a receptacle is attached to the first member. A closure member is attachable to the first member in a fixed position and movable away from the fixed position. A planar wearpad is insertable into the receptacle in the first direction when the closure member is moved away from the fixed position and the second member is positioned on the first member. The stop and closure members inhibit lateral movement of the wearpad in a direction parallel to the plane of the wearpad, and allow movement of the wearpad in a direction transverse to the plane, when the wearpad is positioned in the receptacle. The second member inhibits movement of the wearpad in the direction transverse to the plane.

Abstract: A steering column assembly is provided. The assembly includes an outer jacket, an inner jacket telescopingly disposed within the outer jacket for movement along a longitudinal axis with a cavity defined between the inner and outer jackets. A bushing is radially disposed about the inner jacket within the cavity between the inner and outer jackets. The bushing includes at least one tab engaging the inner jacket to interconnect the bushing to the inner jacket and includes at least one radially projecting pad engaging the outer jacket to frictionally interconnect the bushing to the outer jacket for interlocking the inner and outer jackets.

Abstract: A hemispherical shoe (sliding member) 1 has a flat sliding surface 3, which is quenched to form a quenched portion 7. A part of the quenched sliding surface is partially annealed to form an annealed portion 6. When an oil film pressure acts on the sliding surface 1, the annealed portion 6 is deformed by pressure so that the surface thereof has a concave portion 6A. In the annealed portion 6, a remaining quenched portion 8 may remain at the center part thereof. The concave portion 6A can be used as an oil reservoir or an oil flow path, so that an excellent seizure resistance can be ensured.

Abstract: A device having a rail and a block includes a rail and a block. The rail includes a body and a hollow inside, the hollow inside being located inside the body. The hollow inside of the rail is provided with a lightweight, shock absorption and sound absorption material, and the lightweight, shock absorption and sound absorption material is selected from a group consisting of foam metal material, polystyrene, asbestos, foam, plastic, and rubber. The block is adapted for sliding along the rail to finish a slide path.

Abstract: An all-graphite interferometer bearing assembly is introduced that allows the movement of a movable mirror in a Michelson interferometer without degradation during use. The assembly includes a stationary hollow graphite tube and a movable assembly which includes a mirror and a monolithic graphite member slidably disposed within the bore of the graphite tube that is composed of the same grade of graphite material as the monolithic graphite member. The result is a robust novel moving mirror arrangement in a Michelson interferometer that enables precise mirror alignment control, a long stroke length, excellent vibration damping and reduced sensitivity to external vibrations.

Abstract: A sliding element, and in particular a piston ring, is provided with a DLC coating on a substrate of the sliding element. A material softer than DLC is embedded into the surface of the DLC coating with which the sliding element will come into contact with a sliding partner, against which the sliding element will slide.

Abstract: To provide a sliding member which can control a relationship between dynamic friction force and static friction force, a sliding member 1 constitutes a bearing having a cylindrical shape and its internal circumferential surface is a sliding layer 2 along a shaft. The sliding member 1 is provided a surface of the sliding layer 2 with uneven surface 6. The uneven surface 6 has the line-like projections 6a, vertexes of which are arranged in gridlike fashion, in the embodiment, to prevent an oil film from being formed and to make the dynamic friction force larger and keep the rate of change in the dynamic friction force in relation to the static friction force smaller. The sliding layer is configured so that a porous layer made of alloy material is formed on a surface of a metal substrate and the resin filled into the porous layer is sintered.

Abstract: The invention provides a trolley wheel assembly for a conveyor system, e.g., an overhead conveyor system. In certain embodiments, the wheel assembly includes at least one wheel face having a contour (optionally a funneling configuration and/or one or more surface features) configured to facilitate flow of a fluid toward an open bearing assembly of the wheel assembly. In some embodiments, the wheel assembly includes an inner race, outer race, and bearings having a particular hardness arrangement, optionally together with a polymer wheel having certain filler features. Methods for cleaning such a trolley wheel assembly are also provided.

Abstract: A sliding bearing for structural engineering applications, in particular for civil works such as bridges, buildings, structures that are required at the same time to withstand vertical loads and to allow relative movements and/or rotations, and structures to be protected against seismic events, said bearing having a low friction coefficient and being suitable for being used in severe operating conditions, both due to the loads applied and to particularly high operating temperatures. The bearing, which is of the type comprising a first part (2) connected to a supporting structure (P), a second part (3) connected to an element (G) to be supported by the supporting structure (P) and means suitable for allowing said second part (3) to translate and/or rotate with respect to said first part (2), the means comprising plates (4) and/or strips of a low-friction polymer material, is characterized in that the low-friction material is a polyamide.

Abstract: Provided are a sliding component, such as a mechanical seal ring, which is capable of maintaining superior sliding characteristics even in the long-term continuous use thereof, as well as a mechanical seal, a faucet valve, and a rolling support device, each of which includes the sliding component. The sliding component includes a stationary member, and a movable member contactedly sliding on the stationary member. The stationary member and the movable member are respectively composed of a silicon carbide sintered body containing graphite. The content of the graphite in one of the stationary member and the movable member is at least 4% by mass greater than in the other. Thus, the sliding component includes the stationary member and the movable member which are a combination of those having different contents of graphite. Owing to a high lubricating effect, the superior sliding characteristics can be maintained, permitting a long-term continuous sliding.

Abstract: To provide a sliding member that improves seizure resistance by restraining any exposure of the porous layer and improves abrasion resistance and load resistance. The sliding member 1 constitutes a bearing having a cylindrical shape, an inner circumferential surface of which is a sliding layer 5 with an axis. In the sliding member 1, a porous layer 3 made of alloy material is formed on a surface of a metal base 2 and this porous layer 3 is covered by resin material 4 so that the sliding layer 5 is formed. In the sliding member 1, a particle size of metal powder 30 forming the porous layer 3 is within a range of 15 through 60 ?m, preferably, about 25 through 45 ?m. Further, in the sliding member 1, a thickness of the porous layer 3 is within a range of 0.06 through 0.1 mm and a thickness of the sliding layer 5 is within a range of 0.08 through 0.16 mm The thickness of the sliding layer 5 is set to be thicker on average than the thickness of the porous layer 3 so that the porous layer 3 is not exposed.

Abstract: The invention relates to a system of sliding elements which are formed by a base body and a counter-body. It is the object of the invention to provide a system of sliding element comprising a base body and a counter-body which has a reduced mass with a sufficient strength and which achieves improved properties of friction and wear. The system of sliding elements in accordance with the invention is formed by a counter-body and a base body as friction partners. The base body is formed from a fiber-reinforced polymer material and the counter-body is coated with diamond-like carbon at the surface subject to friction. At least the base body is formed from a textile-reinforced polymer matrix structure.

Abstract: The invention relates to a sliding plug and to a sliding element. The sliding plug, which is inserted into a carrier body of a sliding element, comprises a circumferential surface that has at least one rib extending in the direction of the longitudinal axis of the sliding plug. The sliding element, which is provided with such sliding plugs, preferably comprises a receiving hole having a small-diameter section and having a large-diameter section.

Abstract: Embodiments of the invention are directed to bearing assemblies including one or more superhard bearing elements having one or more grooves formed in a bearing surface thereof, apparatuses, and motor assemblies using the same. In an embodiment, a bearing assembly includes a plurality of superhard bearing elements distributed circumferentially about an axis. Each of the superhard bearing elements includes a bearing surface. At least one of the plurality of superhard bearing elements includes one or more grooves formed in the bearing surface thereof. The bearing assembly also includes a support ring that carries the superhard bearing elements.

Abstract: A sliding element comprises a metallic support layer, a metallic porous carrier layer applied thereon, and a sliding layer which has a thickness D applied on the carrier layer. The sliding layer comprises a first material containing a thermoplastic matrix and a second material containing PTFE. The second material is impregnated in the first material, which form a gradient over a depth T, where T?D in a surface area of the sliding layer.

Abstract: A slide bearing can include a metal support, a primer layer, an adhesive layer applied directly thereto, and a sliding layer applied to the adhesive layer. The primer layer can include an oligomeric condensate of at least one silanol selected from the group having the formula: wherein x is 1 or 2, y is 0 or 1. The moieties R1 and R2 can be the same or different. The moieties R1 and R2 can be selected from the group consisting of methyl, ethyl, n-propyl, i-propyl, and a functionalized alkyl group R?—(CH2)z—, wherein z is at least 1. Slide bearings comprising a primer system based on silanol oligomeric condensates show improved peel strength than their analogous slide bearings lacking the primer system.

Abstract: The present invention is applied to a tribological pair comprising two metal pieces, a first of them having a movable contact surface which provides friction in relation to a respective contact surface of a second of said metal pieces. According to the present invention, the first metal piece has its contact surface defined by a coating formed: by a first surface layer in a material harder than that of the first metal piece; and by a second surface layer, disposed onto the first surface layer and in a material defining a coating which reduces the chemical affinity in relation to the contact surface of the second metal piece of the tribological pair, in order to provide, to said tribological pair, a lower friction coefficient in relation to the tribological pair deprived of said coating.