Daimler Ag

Daimler Chrysler Ag

Wolfgang Pellkofer

Patrick Izquierdo

Martin Hartweg

Karl Holdik

Harald Pfeffinger

Johannes Leweux

Jens Boehm

Dezsoe Schilling

Dirk Becker

Tobias Hercke

Christian Russer

Michael Gruener

Marcus Brand

The invention relates to a process for roughening metal surfaces to improve adhesion of layers which are thermally sprayed thereon, in that in a first process step recesses or depressions () are introduced into the surface in a material-detaching or material-removing treatment so that the protruding metal of the surface forms raised microstructures (), in particular projections, ridges, protuberances or bumps, these microstructures being reworked in at least a second process step by shaping and/or breaking so that a significant proportion of the structures form undercuts () in relation to the surface.

Surface conditioning for thermal spray layers

Piston pin for a connecting rod in a reciprocating internal combustion engine, wherein the piston pin carries at least in the area of the running surface a thermal sprayed slide layer of a metallic bearing material or slide bearing material, as well as reciprocating internal combustion engine with a connecting rod with small and with large connecting rod eye, wherein at least the running surface of one of the piston pins is formed of a thermal sprayed slide layer of a metallic bearing material, which exhibits a lower hardness than the running surface of the corresponding connecting rod eye and process for manufacturing a described piston pin with the steps of a extrusion molding or machining a piston pin preform, introduction of a recess in the area which will later become the running surface, roughening the outer surface in the area of the recess, application of a coating of a bearing material by a thermal spray process.

Piston pin with slide layer for connecting rod eye for internal combustion engines

In an internal combustion engine for a motor vehicle, having a piston bearing surface divided into regions of different loading and having recesses for retaining lubricant arranged at distances which are shorter in regions of high loading than in regions of lower loading in a region with high loading, the distance between the recesses decreases from one recess to the next in the direction toward top dead center area with the smallest distance being at the top dead center position of the piston.

Internal combustion engine

Growing community of inventors

Ulm, Germany

Wolfgang Pellkofer