Corrosion resistant coatings for cylinder bore applications in passenger car engines

摘要

Thermally sprayed cylinder bore coatings give the opportunity to use tailored materials in the cylinder bore of passenger car engines with aluminium crankcases. For some applications coating material feedstock with ceramic content is needed as well as solid lubricants for high performance engines in motorsports. A relatively new demand is a certain resistance against corrosion that is caused by new using profiles and alternative fuels. Compared to cast in or slip-fit liners the material of thermally sprayed bore surfaces can easily be adapted to different markets and user profiles without changing the engine block. Content of this work is an investigation of the capability and performance of two different steel wires (1.4820 (X12 CrNi 25-4) and 1.4016 (X6 Cr17)) to be used as corrosion resistant coatings for cylinder bores in light metal crankcases. The materials were sprayed by a PTWA spraying system onto aluminium crankcases (alloy A319) which were mechanically roughened prior coating. The coatings have then been honed with different honing structures and their performance will be analysed by wear tests as well as tensile strength and hardness measuring.