Abstract: An internal combustion engine may include at least one cylinder and at least one hollow-heat valve. The at least one hollow-head valve may include a valve shaft and a valve head, and may be guided in a valve shaft guide. The engine may also include at least one valve seat ring on which the valve head sealingly lies when the at least one hollow-head valve is closed. The engine may additionally include a valve shaft seal with at least two seal lips and oil disposed between the valve shaft and the valve shaft guide. The at least one valve seat ring may be composed of a sintered metal including infiltrated copper. The valve shaft may include one of a chromium-containing coating and a boron carbide-containing coating.

Abstract: A method for producing a valve seat ring via powder metallurgy may include compacting a powder mixture including 4% by weight to 16% by weight particles of cobalt to form the valve seat ring. The method may also include sintering the powder mixture after compacting the powder mixture. Before compacting the powder mixture, 80% of the particles of cobalt may have a particle diameter of approximately 4.4 ?m to 17.5 ?m.

Abstract: A method for producing a powder-metallurgical product, in particular a bearing element or a motor component, is provided. According to the method, a metal powder, typically with a grain size between 2 ?m and 15 ?m, is melt-metallurgically produced and agglomerated into a powder mixture having a grain size smaller than 400 ?m by organic binders and waxes. Subsequently, the agglomerated powder mixture is formed into a green body typically by way of uniaxial pressing and the formed green body thermally debindered. Finally, the debindered green body is sintered typically at temperatures of 1000° C. to 1300° C. and the sintered body reworked into the powder-metallurgical product.

Abstract: A method for producing a copper-infiltrated valve seat ring and a valve seat ring are disclosed. The method includes introducing a copper powder and a functional material powder mixture into a joint cavity, simultaneously forming the copper powder and the functional material powder mixture into a green body comprising a functional section and a copper section in the joint cavity by the mold element, and sintering the green body formed in step b) to produce the valve seat ring where the copper section liquefies during the sintering and infiltrates pores present in the functional section.

Abstract: A method for producing a powder-metallurgical product may include providing a powder mixture, forming the powder mixture into a green body, and sintering the green body to form a resulting powder-metallurgical product. The powder mixture may include a first hard phase, a second hard phase, 0 to 1.8% by weight of graphite, 0 to 5% by weight each of cobalt, tri-iron phosphide, copper, bronze, phosphorous, sulphur, calcium fluoride and molybdenum, 0.1 to 1.8% by weight of a pressing aid and a flow improver, and a remaining proportion that is an iron-base powder. The first hard phase may include 52 to 78% by weight of molybdenum, 0 to 2% by weight of silicon, 0 to 1.5% by weight of copper, and a remaining weight proportion of iron and production-related contaminations. The second hard phase may include 0 to 0.8% by weight of manganese and less than 0.1% by weight of carbon.

Abstract: A method for mounting a valve seat ring on a cylinder head of an internal combustion engine includes providing a valve seat ring, which has a ring height, and which is measured along an axial direction. The valve seat ring includes a support portion made of a support material and a functional portion made of a functional material. The valve seat ring is arranged on the cylinder head and the support portion of the support material is at least partially removed, so that the ring height of the valve seat ring is reduced.

Abstract: An internal combustion engine may include at least one cylinder and at least one hollow-heat valve. The at least one hollow-head valve may include a valve shaft and a valve head, and may be guided in a valve shaft guide. The engine may also include at least one valve seat ring on which the valve head sealingly lies when the at least one hollow-head valve is closed. The engine may additionally include a valve shaft seal with at least two seal lips and oil disposed between the valve shaft and the valve shaft guide. The at least one valve seat ring may be composed of a sintered metal including infiltrated copper. The valve shaft may include one of a chromium-containing coating and a boron carbide-containing coating.

Abstract: A method for producing a copper-infiltrated valve seat ring and a valve seat ring are disclosed. The method includes introducing a copper powder and a functional material powder mixture into a joint cavity, simultaneously forming the copper powder and the functional material powder mixture into a green body comprising a functional section and a copper section in the joint cavity by the mold element, and sintering the green body formed in step b) to produce the valve seat ring where the copper section liquefies during the sintering and infiltrates pores present in the functional section.

Abstract: A method for mounting a valve seat ring on a cylinder head of an internal combustion engine includes providing a valve seat ring, which has a ring height, and which is measured along an axial direction. The valve seat ring includes a support portion made of a support material and a functional portion made of a functional material. The valve seat ring is arranged on the cylinder head and the support portion of the support material is at least partially removed, so that the ring height of the valve seat ring is reduced.

Abstract: A tribological system may include a valve seat ring composed of a sintered material and a valve having a surface at least in a seat region that may be at least one of (i) untreated, (ii) hardened, and (iii) plated. The sintered material may be a pressed and sintered powder mixture having a composition that may include (i) 5 to 45 wt % of at least one Fe-based hard phase, (ii) 0 to 2 wt % of each of graphite particles, MnS powder, MoS2 powder, and FeP powder, (iii) 0 to 7 wt % copper powder and 0 to 4 wt % Co powder, (iv) 0.1 to 1.0 wt % of a pressing aid, (v) a high-speed steel having a composition including 14-18 wt % Cr, 1.2-1.9 wt % C, 0.1-0.9 wt % Si, 0.5-2.5 wt % of each of V, W, and Mo, and (vi) a balance of Fe and production-related impurities in quantities of <1.5 wt %.

Abstract: A method for producing a powder-metallurgical product, in particular a bearing element or a motor component, is provided. According to the method, a metal powder, typically with a grain size between 2 ?m and 15 ?m, is melt-metallurgically produced and agglomerated into a powder mixture having a grain size smaller than 400 ?m by organic binders and waxes. Subsequently, the agglomerated powder mixture is formed into a green body typically by way of uniaxial pressing and the formed green body thermally debindered. Finally, the debindered green body is sintered typically at temperatures of 1000° C. to 1300° C. and the sintered body reworked into the powder-metallurgical product.

Abstract: A method for producing a powder-metallurgical product may include providing a powder mixture, forming the powder mixture into a green body, and sintering the green body to form a resulting powder-metallurgical product. The powder mixture may include a first hard phase, a second hard phase, 0 to 1.8% by weight of graphite, 0 to 5% by weight each of cobalt, tri-iron phosphide, copper, bronze, phosphorous, sulphur, calcium fluoride and molybdenum, 0.1 to 1.8% by weight of a pressing aid and a flow improver, and a remaining proportion that is an iron-base powder. The first hard phase may include 52 to 78% by weight of molybdenum, 0 to 2% by weight of silicon, 0 to 1.5% by weight of copper, and a remaining weight proportion of iron and production-related contaminations. The second hard phase may include 0 to 0.8% by weight of manganese and less than 0.1% by weight of carbon.

Abstract: A valve seat ring and a method for producing the same may include a first material and a second material. The first material may be composed of approximately 15 to 30% by weight of Mo, approximately 5 to 30% by weight of chromium, approximately 0 to 5% by weight of Si, approximately 0 to 2% by weight of C, and up to 5% by weight of other elements and a portion of Co. The second material may be composed of approximately 10 to 12% by weight of Cr, approximately 0.5 to 0.8% by weight of Mn, approximately 0.5 to 1% by weight of Si, approximately 0.5 to 0.9% by weight of C, up to approximately 3% by weight of other elements and a reminder of Fe.

Abstract: A method for producing a valve seat ring via powder metallurgy may include compacting a powder mixture including 4% by weight to 16% by weight particles of cobalt to form the valve seat ring. The method may also include sintering the powder mixture after compacting the powder mixture. Before compacting the powder mixture, 80% of the particles of cobalt may have a particle diameter of approximately 4.4 ?m to 17.5 ?m.

Abstract: A tribological system may include a valve seat ring composed of a sintered material and a valve having a surface at least in a seat region that may be at least one of (i) untreated, (ii) hardened, and (iii) plated. The sintered material may be a pressed and sintered powder mixture having a composition that may include (i) 5 to 45 wt % of at least one Fe-based hard phase, (ii) 0 to 2 wt % of each of graphite particles, MnS powder, MoS2 powder, and FeP powder, (iii) 0 to 7 wt % copper powder and 0 to 4 wt % Co powder, (iv) 0.1 to 1.0 wt % of a pressing aid, (v) a high-speed steel having a composition including 14-18 wt % Cr, 1.2-1.9 wt % C, 0.1-0.9 wt % Si, 0.5-2.5 wt % of each of V, W, and Mo, and (vi) a balance of Fe and production-related impurities in quantities of <1.5 wt %.

Abstract: A valve seat ring and a method for producing the same may include a first material and a second material. The first material may be composed of approximately 15 to 30% by weight of Mo, approximately 5 to 30% by weight of chromium, approximately 0 to 5% by weight of Si, approximately 0 to 2% by weight of C, and up to 5% by weight of other elements and a portion of Co. The second material may be composed of approximately 10 to 12% by weight of Cr, approximately 0.5 to 0.8% by weight of Mn, approximately 0.5 to 1% by weight of Si, approximately 0.5 to 0.9% by weight of C, up to approximately 3% by weight of other elements and a reminder of Fe.