The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 2000
Filed:
Nov. 12, 1997
Franz Ruckert, Ostfildern, DE;
Peter Stocker, Sulzbach/Murr, DE;
Roland Biedermann, Stuttgart, DE;
Roland Rieger, Weinstadt, DE;
DaimlerChrysler AG, Stuttgart, DE;
Abstract
A cylinder liner cast into a reciprocating piston engine made of a supereutectic aluminum/silicon alloy which is free of mixed-in particles of hard material and which is composed in such a way that fine silicon primary crystals and intermetallic particles automatically form from the melt as hard particles. A blank is allowed to grow from finely sprayed melt droplets by spray compaction, with a fine distribution of hard particles being produced by setting the spray for small melt droplets. The blank can then be formed by cold extrusion to create a shape approximating the cylinder lining. After premachining, the surface is fine machined, honed in at least one stage and then the hard particles lying at the surface are mechanically or chemically exposed, forming plateau areas of hard particles which project above the remaining surface of the base microstructure of the alloy. The mechanical exposure of the primary crystals or particles is carried out by a honing process using felt strips which are cylindrically shaped on the outside and a slurry of SiC particles in honing oil. The chemical exposure of the primary crystals or particles is carried out by using aqueous alkali. The fine-grained, hard particles formed from the melt and also the mechanical exposure of the hard particles on the surface of the cylinder results not only in high wear resistance and high contact area of the surface, but also in gentle treatment of the piston and its rings.