Laser honing0 pages

Laser Honing

Gehring

Rising customer expectations

and future exhaust and emission

laws place extensive requirements

on the oil and fuel consumption of

gaseoline and diesel engines. The

laser honing developed by Gehring

has become an international stan-

dard. For both diesel and gaseoline

engines, the laser structuring of the

cylinder is currently applied in the

range of the upper piston rever-

sal point. The combination of laser

structuring and honing of cylinder

bore surfaces is known as laser

honing.

Objective of laser honing

In principle, the frictional forces

in the tribological system consiting

of piston ring and cylinder bore

are to be reduced. As a contributi-

on to the future viability of internal

combustion engines, laser honing

provides an opportunity to improve

exhaust emissions so that the future

exhaust limits such as Euro 5 and

Euro 6 are easier to achieve.

Principles of laser honing

The combined honing and laser

structuring of cylinder bore surfaces

is considered laser honing. During

this process the engine block first

undergoes the conventional rough

and intermediate honing step in

order to achieve the desired base

profile for the laser structuring.

Microscopic pockets, the engine-

specific laser structure, are created

into the cylinder bore surface by

means of a laser beam. The subse-

quent final steps, deburring and

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Process sequence for the laser structuring of cylinder bores

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finish honing, remove the melt

protrusions arising from the laser

processing to create an extremely

fine surface.

Cylinder bore after laser honing

Structure after laser honing

Structure after finishing work