Cylinder liners for aluminum motor blocks and methods of production

摘要

A generally hollow cylindrical piston liner for insertion in an internal combustion engine between a piston and an engine block has a cast aluminum piston liner body with cast iron engine block contact surface structure extending therefrom and securely thermally bonded thereto for exhibiting a roughened outer contact surface adapted to interface with an engine block, and its method of manfacture. The cast iron contact surface member roughened surface is generated by introducing in a first mold step a mold wash substance that generates a substantially uniform bubble pattern within a mold wash matrix layer into which the molten iron is poured to thereby produce a roughened iron interface surface. The aluminum piston liner is then bonded to the iron liner in a second molding step by pouring molten aluminum into a pre-heated mold to bond the cast iron engine block surface structure to the aluminum liner. During the solidification stages, the molds are centrifugally rotated about the piston liner cylinder axis to established the required manufacturing precision required for large diameter piston liners. The piston liners typically form a series of circumferal motor block contact ribs spaced proportionately along the liner length to extend from a cylindrical body for carrying the cast iron contact surface structure.