Light metal cylinder block, method of producing same and device for carrying out the method
AssigneeVAW Aluminum AG
InventorFranz Josef Feikus
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Abstract
Thc present invention includes a light metal cylinder block comprising a cylinder running face which is coated with silicon. The invention also includes a method by which the silicon is applied to the running face comprising melting powder metal silicon, which is fired at the face in a powdered metal beam, under heat of a laser which is fired at the running face at the point of impact of the powdered beam. Furthermore the invention includes a device with which the cylinder block may be manufactured.
Claims18
A light metal cylinder block having at least one wear-resistant and tribologically optimized cylinder running face compromising a light metal matrix alloy with a finely, dispersed surface layer containing primary silicon phases wherein the primary silicon comprises uniformly distributed approximately roundly formed grains with a medium grain diameter ranging between about 1 and about 10 μm and Wherein the surface layer contains about 10 to about 14% AlSi eutectic, about 5 to about 20% primary silicon, the remainder being pure Al phase, and wherein the minimum hardness of the surface amounts to about 160 HV.
A light metal cylinder block having at least one wear-resistant and tribologically optimized cylinder running face, comprising a light metal matrix alloy with a finely dispersed surface layer which contains primary silicon precipitations and which, as a pure diffusion layer comprises an alloyed-on zone high in precipitations and of interface zones low in segregations, wherein the segregations comprise uniformly distributed. approximately roundly formed primary Silicon grains with a mean grain diameter- ranging between about 1 and about 10 μm and herein the alloyed-on zone comprises about 10 to about 14% AlSi cutectic about 5 to about 20% primary silicon. the remainder being pure aluminum phase. and comprises a minimum hardness of about 160 HV
A method of producing a light metal cylinder block having at least one wear-resistant and tribologically optimized cylinder running face comprising a light metal matrix alloy and a powder material which contains a hard material and which is present in the form of a finely dispersed surface layer with primary silicon precipitations in the light metal matrix, using a gravity low-pressure or high-pressure die casting method with subsequent surface treatment by parallel laser and powder beams wherein the laser beam is guided in a strip width of at least about 2 mm transversely to the direction of feed across the matrix surface and wherein it is only in the point of impact of the laser beam on the light metal matrix surface in a contact time of about 0.1 to about 0.5 seconds, that the powder is heated to melting temperature and diffused in.
A device for coating the a running surface of a hollow cylinder comprising powder supply means (1) a laser beam device (2) and a focusing system (3) with a deflecting mirror (4), characterized in that the powder supply means (1) and the laser beam device (2) are guided parallel relative to one another in the radial and axial direction of the hollow cylinder. that the focusing system (3) comprises a linear beam exit with a beam width of about 2.0 to about 2.5 mm;
- and that the powder supply means are provided with a metering device by means of which the volume flow of the powder can be set as a function of the speed of feed of the laser beam.
Dependencies are inferred from the claim text.