As seen in Figure 1 when electrochemical etching is compared to laser marking it
appears dull and two dimensional. Laser marking allows for more ef! cient removal of material
which produces a three dimensional characteristic to the mark. This allows for improved
readability and wear resistance. The electrochemical process is a controlled corrosion of the
metallic surface which produces a darkened mark. Since, this process involves an aggressive
chemical reaction it can be an initiation site for future corrosion. Laser marking is an ablative
process which selectively removes the material of interest. A laser mark only takes seconds to
complete and can produce feature sizes down to 0.005” and engrave up to 0.020” deep. Since
the process is controlled via a computer interface no masks are required. The laser marking
process is completely non-contact which makes it easily automated and repeatable. In addition
to being non-contact laser marking also is much more " exible regarding the addition of images
and sequential alpha-numeric characters to the part. Virtually any image ! le or alpha-numeric
character set can be laser marked onto a part. This includes company logos, part numbers, 1-
D and 2-D bar codes.
Overall, there are many choices for part identi! cation. Electrochemical etching
has been used in many applications and will continue to be implemented because of
its accessibility. However, laser marking continues to gain ground on many identi! cation
applications and is being speci! ed by more industries looking for a non-contact, clean, and
reliable way to identify components