Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer or a triple layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer. The tribological coating may be provided with varying thickness such that its thickness increases gradually from 90° towards 0° in a first radial direction of the piston ring and from 270° towards 360° in a second radial direction of the piston ring reaching its maximum value in the region of 0° and 360°, i.e. the tips of the piston ring.

Abstract: A piston ring includes a split annular body having an outer circumferential surface, an intermediate coating on the outer circumferential surface, a first layer on the intermediate coating, the first layer having a first hardness and a first porosity, and a second layer on the first layer, the second layer having a second hardness that is less than the first hardness, and having a second porosity that is greater than the first porosity.

Abstract: A piston ring includes a split annular body having an outer circumferential surface, an intermediate coating on the outer circumferential surface, a first layer on the intermediate coating, the first layer having a first hardness and a first porosity, and a second layer on the first layer, the second layer having a second hardness that is less than the first hardness, and having a second porosity that is greater than the first porosity.

Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer or a triple layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer. The tribological coating may be provided with varying thickness such that its thickness increases gradually from 90° towards 0° in a first radial direction of the piston ring and from 270° towards 360° in a second radial direction of the piston ring reaching its maximum value in the region of 0° and 360°, i.e. the tips of the piston ring.

Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer or a triple layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer. The tribological coating may be provided with varying thickness such that its thickness increases gradually from 90° towards 0° in a first radial direction of the piston ring and from 270° towards 360° in a second radial direction of the piston ring reaching its maximum value in the region of 0° and 360°, i.e. the tips of the piston ring.

Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer.

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 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 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 piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer or a triple layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer. The tribological coating may be provided with varying thickness such that its thickness increases gradually from 90° towards 0° in a first radial direction of the piston ring and from 270° towards 360° in a second radial direction of the piston ring reaching its maximum value in the region of 0° and 360°, i.e. the tips of the piston ring.

Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer or a triple layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer. The tribological coating may be provided with varying thickness such that its thickness increases gradually from 90° towards 0° in a first radial direction of the piston ring and from 270° towards 360° in a second radial direction of the piston ring reaching its maximum value in the region of 0° and 360°, i.e. the tips of the piston ring.

Abstract: A piston ring and a method of manufacturing a piston ring for a piston of a reciprocating internal combustion engine. The piston ring comprises a body having an outer circumferential surface. A tribological coating is formed on the outer circumferential surface of the body. The tribological coating has a dual layer structure and includes a relatively hard base layer and a relatively porous top layer overlying the base layer.

Abstract: A bearing lining has a bearing backing layer provided with a coating comprising a first overlay layer and a second overlay layer, the first overlay layer being provided between the bearing backing layer and the second overlay layer. The first and second overlay layers each comprise a matrix material and a soft-phase material that is substantially insoluble in the matrix and dispersed within the matrix as soft-phase particles. The first overlay layer comprises a higher proportion by weight of a grain size reduction additive than the second overlay layer.

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 vapour 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 process for coating a cylinder or a liner of an internal combustion engine may involve a plasma assisted chemical vapour deposition (PACVD) technique. The process may include placing a component to be coated in a PACVD system; forming a negative pressure within the system in an inert atmosphere including argon, hydrogen, or a mixture thereof; activating a surface of the component at a bias voltage of 300 to 550 Vbias; performing an ionization of the component at a bias voltage of 800 to 1200 Vbias; depositing an adhesive layer having a precursor element on the surface of the component; depositing a transition layer having a gradient content of increasing amorphous carbon and decreasing precursor element; and depositing an upper layer composed of an amorphous carbon with the precursor element.

Abstract: The invention relates to a piston ring (10, 110, 210, 310, 410, 510, 610) for pistons of internal combustion engines, having a ring running surface (14), a ring back (11), an upper ring flank (12), a lower ring flank (13), and two ring joint ends spaced apart by a gap (15). According to the invention, at least one opening (17, 121, 217, 223, 325, 407) is provided in the ring running surface (14), which opening forms a fluid connection between the ring running surface (14) and the ring back (11) or a ring flank (12, 13).

Abstract: The invention relates to a piston ring (10, 110, 210, 310, 410, 510, 610) for pistons of internal combustion engines, having a ring running surface (14), a ring back (11), an upper ring flank (12), a lower ring flank (13), and two ring joint ends spaced apart by a gap (15). According to the invention, at least one opening (17, 121, 217, 223, 325, 407) is provided in the ring running surface (14), which opening forms a fluid connection between the ring running surface (14) and the ring back (11) or a ring flank (12, 13).

Abstract: A slide component, used in internal combustion engines, provided with a metal-based substrate material and a protective liner (R), with the slide component having at least two main elements, the first one composed by an element with high resistance to corrosion, and the second element providing increase of the resistance to wear and/or presenting lower friction than the substrate material, both of them covering at least one of the surfaces of the slide component.

Abstract: A bearing lining has a bearing backing layer provided with a coating comprising a first overlay layer and a second overlay layer, the first overlay layer being provided between the bearing backing layer and the second overlay layer. The first and second overlay layers each comprise a matrix material and a soft-phase material that is substantially insoluble in the matrix and dispersed within the matrix as soft-phase particles. The first overlay layer comprises a higher proportion by weight of a grain size reduction additive than the second overlay layer.

Abstract: The invention relates to a piston ring for internal combustion engines, the piston ring comprises a steel or cast iron base material with a coating of chromium nitride deposited by a physical vapor deposition process on a sliding surface of the piston ring, wherein the coating is composed of a columnar crystal structure of CrN with the following features: (a) an oxygen content in solid solution of 0.5 to 2.5 wt %; (b) a content of uniformly dispersed micro-pores of less than 10% in volume of the coating; and (c) an X-ray diffraction intensity ratio of (111) planes to (200) planes parallel to the surface in the range of 0.80 to 1.20.