Abstract: A piston ring for internal combustion engines provided with a ferrous alloy base includes an annular outer surface on which a coating including at least one outer layer is applied deposited on an adhesive layer, the outer layer being provided with a variable thickness, in such a way that the thickness of the outer layer gradually increases from 90° and 270° towards 0° and 360° respectively, with the thickness attaining its maximum value in the region of 10° and 350° and slightly decreasing towards 0° and 360° so as to ensure an optimal working condition, minimizing the contact pressure and consequently the accelerated wear in the vicinities of the ends of the ring, in addition to preventing and/or impeding the detachment of the outer layer of the coating.

Abstract: A valve for an internal-combustion engine may include a body. The body may include a titanium alloy. At least one region of the body may include a nitrided layer. The nitrided layer may include at least one of titanium nitrides and aluminium-titanium nitrides.

Abstract: A piston ring may have a base with a sliding external surface, an internal surface, an upper surface, and a lower surface, the external surface having chamfered edges. The external surface, the internal surface, the upper surface, the lower surface, and the chamfered edges may have a coating provided with a nitrided first layer having a thickness of up to 2% of a nominal axial thickness of the ring when applied to the upper surface and the lower surface, and a thickness of up to 10% in relation to the thickness of the first layer applied to the upper surface and the lower surfaces when applied to the external surface and to the chamfered edges. The external surface and the chamfered edges may include a sliding layer having one of a hard chromium or ceramic chromium plated coating, the sliding layer being applied on the first layer, the sliding layer having a thickness of between 80 and 175 microns.

Abstract: An air filter for a fresh air system of an internal combustion engine may include a filter housing, a filter element, and an inner frame. The filter housing may include a housing pot, a housing lid, a raw air inlet, and a pure air outlet. The filter element may include an annular filter body, a first end plate, and a second end plate. The second end plate may include an annular first seal bearing sealingly against the housing pot, an annular second seal bearing sealingly against the inner frame, and at least one of at least one first annular web and at least one second annular web. The first seal may be coupled on a free end side of the at least one first annular web. The second seal may be coupled on a free end side of the at least one second annular web.

Abstract: A piston ring for a piston of an internal combustion engine may include a body composed of a ferrous material. The body may have an upper portion, a lower portion opposed to the upper portion, an internal portion configured to face towards a piston groove and an external portion opposed to the internal portion. An upper chamfer may be disposed between the upper portion and the external portion. A lower chamfer may be disposed between the lower portion and the external portion. The upper portion, the lower portion and the internal portion may each have a nitrided layer. The external portion, the upper chamfer and the lower chamfer may include at least one ion plated coating layer. The nitrided portion in at least a superficial layer may have a hardness of 700 HV or less.

Abstract: An air filter for a fresh air system of an internal combustion engine may include a filter housing including a housing lid and a filter element arranged exchangeably in the filter housing separating a raw side from a pure side. The filter element may include an annular filter body, a first end plate, and a second end plate. A dust collector space may be disposed in the filter housing on the raw side and may be delimited axially by the housing lid and the first end plate. The housing lid may have a step which may radially delimit the dust collector space. A connection may be disposed in a circumferential section of the dust collector space which is not bordered by the step. The step may have a radial aperture fluidically connecting the dust collector space to a discharge stub, the radial aperture arranged diametrically opposite the connection.

Abstract: A thrust washer for an internal combustion engine may include a body. The body may have a slip surface and a planar contact surface associated with an engine block. The slip surface may have a surface profile the may include at least one ramp section, at least one flat horizontal section, and at least one oil channel. The at least one ramp section and the at least one flat horizontal section may be connected via an asymptotic curve. The at least one ramp section may extend asymptotically toward the at least one flat horizontal section. The at least one ramp section may have an angular length of 45° or less, the at least one flat horizontal section may have an angular length of 45° or less, and the at least one oil channel may have an angular length of 20° or less.

Abstract: A thrust washer for an internal combustion engine may include a metal base having a contact surface and a slip surface. The contact surface may be in operative communication with an engine block. The slip surface may define at least one ramp section, at least one flat horizontal section, and at least one oil channel. The ramp section and the flat horizontal section may be connected via an asymptotic curved surface. The ramp section may be positioned asymptotically towards the flat horizontal section.

Abstract: A sliding element, for example a piston ring for an internal combustion engine, may include a sliding face, an adhesive layer disposed on the sliding face, and a coating disposed over the adhesive layer. The coating may be composed of an amorphous carbon material. The coating may have a ratio between sp3 bonds and sp2 bonds that indicates a predominance of sp2 bonds. The coating may have a roughness profile including a value of Rpk of ?0.15 ?m and a value of Rz of 0.7?Rz?1.5 ?m.

Abstract: A piston ring may include a stainless steel base having between 8% and 15% by weight of chromium, together with other elements and impurities, and having a hardness between 350 HV and 420 HV. The piston ring may also include a superficial nitrided layer having a depth of no more than 60 ?m and an average hardness measured upon the surface exceeding 800 HV. The nitrided layer may include a plurality of nitride particles, which may have a maximum size of 5 ?m and may be distributed over between 4% and 8% of an area of the nitrided layer.

Abstract: A piston ring for an internal combustion engine may include a substantially annular base of a ferrous alloy upon which is applied a coating. The coating may have a first bonding layer and at least a first external layer or a second external layer deposited upon the first bonding layer up to a maximum of 100 micrometers in thickness of a plurality of sequentially deposited first and second external layers. The first external layer may include a nitride of a doped metal chemical element, a doping element being aluminum. The second external layer may include a nitride of the metal chemical element. The first external layer may have a thickness greater than at least once a thickness of the second external layer and less than ten times the thickness of the second external layer.

Abstract: A cylinder liner for insertion into an aluminum internal-combustion engine block may include a cylindrical body of cast iron having a circumferential external surface. The cylinder liner may also have a coating deposited on and surrounding the external surface. The external surface may have a specific roughness, and the coating may include at least 98% by volume of pure nickel, and a remainder composed of impurities.

Abstract: A piston ring for an internal-combustion engine may include a body having a substantially annular external surface and a physical vapor deposition coating layer disposed on the external surface. The body may include a gap defined between a first end and a second end. The piston ring may also include a first half in a region of the gap and a second half opposite the first half. The coating layer of the first half may have a thickness gradient, and the coating layer may define a greater thickness in a vicinity of the first end and the second end and a reduced thickness in regions further away from the vicinity of the first end and the second end. The coating layer of the second half may have a uniform thickness.

Abstract: A sliding element for internal combustion engines may include a sliding face upon which are deposited, from the sliding face outwards, an adhesive layer and a coating of hard amorphous carbon. The coating may present a proportion of sp3 to sp2 ranging from 0.42 to 2.33 and at least one of an Rmr (0.2-0.5) profile greater than at least 25% and/or an Rmr (0.3-0.5) profile greater than at least 50%.

Abstract: A piston ring in cast tool steels including a ring of a tempered material having a chemical composition including a percent weight concentration of C from 0.80 to 1.40, Cr from 2.50 to 4.20, Mn from 0.10 to 1.00, Mo from 1.00 to 2.00, Nb from 2.50 to 4.50, P of no more than 0.05, S of no more than 0.05, Si from 0.10 to 1.00, Ti from 0.10 to 0.30, V from 1.00 to 3.00, W from 1.00 to 3.00, and a remaining concentration balance of Fe. The tempered material may have a microstructure including a matrix of tempered martensite with precipitation of at least one of secondary M2C carbides and MC carbides, M being at least one of V, Mo, Cr, and W. The microstructure may include NbC eutectic carbides having a cubic morphology. The tempered material may have a hardness from approximately 400 HV to 800 HV.

Abstract: A sliding combination for use in an internal combustion engine may include at least one cylinder liner defining an internal sliding surface and a ring having an external lateral sliding surface. The external sliding surface of the ring may slide in relation to the internal sliding surface of the liner. The external sliding surface of the ring may include a first coating of a physical vapor deposited metal nitride in sliding contact with a second coating of a diamond-like carbon (DLC) material disposed on the internal sliding surface of the liner.

Abstract: A cylinder liner for an internal combustion engine may include a hollow cylindrical body. The body may include an internal surface having a longitudinal/axial length. The internal surface may be divided into at least two portions along the longitudinal/axial length. The at least two portions may respectively include a specific value of roughness and a predefined length.

Abstract: A bushing may include a support surface and a sliding surface having a perimeter midpoint. The sliding surface of the bushing may have a convex profile in relation to a cross section of the bushing. The convex profile may be offset from the perimeter midpoint of the sliding surface of the bushing.

Abstract: A wet cylinder liner for internal combustion engines may include a cylindrical body composed of a ferrous alloy having a circumferential outer surface. The cylindrical body may include a first layer and a second layer disposed sequentially on the outer surface. The first layer may include at least one of at least one silicon and at least one two-component epoxy adhesive. The second layer may include a silane-elastomer compound. The silane-elastomer compound may include nanoparticles of silicon oxide and an adhesion modifier additive. The second layer may be configured as an interface between a cooling fluid and the first layer, as well as to resist erosion by cavitation. The first layer may facilitate an interface for resistance at high temperatures.

Abstract: A sliding element for internal combustion engines may include a ferrous base provided with a film applied upon a sliding surface. The film may have, sequentially, a metal connecting layer, a transitional layer, and a contact layer. The transitional layer may include a carbide containing a metal element. The contact layer may contain DLC (diamond-like carbon) doped with the metal element of the transitional layer, the DLC containing a maximum of 2% hydrogen by weight. An atomic ratio between metal and carbon in the contact layer in terms of a ratio Me/C is equal to or less than 0.1.