Daimler Chrysler Ag

Franz R&uuml;ckert

Peter Stocker

Roland Rieger

Roland Biedermann

A one-piece steering wheel skeleton is produced by die casting an aluminum alloy of the Al&mdash;Mg&mdash;Mn type. Such a steering wheel skeleton has a high strength in combination with a high ductility. An object is to further increase the ductility of such a steering wheel skeleton, so that severe deformation of the steering wheel skeleton without breakage of the steering wheel spokes occurs under the influence of a very high acting force. To achieve this, the steering wheel skeleton undergoes a heat treatment in age hardening at elevated temperatures and then is cooled in stationary air. A steering wheel skeleton heat treated in this way can endure at least 30% greater deformation without breakage of the spokes in comparison with an untreated workpiece.

Steering wheel skeleton

The invention relates to a cylinder liner made from a hypereutectic aluminum/silicon alloy which is surrounded by a surround casting material, which is characterized in that the minimum ratio of the wall thickness of the surround casting material of the cylinder liner is 1.4.

Cylinder liner

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 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.

Cylinder liner comprising a supereutectic aluminum/silicon alloy for sealing into a crankcase of a reciprocating piston engine

Surface activation is intended to ensure that a cylinder liner can be anchored in the casting material of a light-metal crankcase with greater bonding. For surface activation, the surface of the cylinder liner is roughened mechanically. Advantageously, copper particles are also implanted into the treated surface. It is necessary to ensure that the time span between surface activation and casting-in is short. Moreover, the activated surface, as far as possible, should not be touched by hand.

Growing community of inventors

Ostfildern, Germany

Franz Rückert

Growing community of inventors

Ostfildern, Germany

Franz R&uuml;ckert

Franz Rückert