Identification marking by means of laser peening

Patent · Tue Jan 01 00:00:00 EST 2002

OSTI ID:874614

Hackel, Lloyd A ^[1]; Dane, C Brent ^[1]; Harris, Fritz ^[2]

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1. Livermore, CA
2. Rocklin, CA

The invention is a method and apparatus for marking components by inducing a shock wave on the surface that results in an indented (strained) layer and a residual compressive stress in the surface layer. One embodiment of the laser peenmarking system rapidly imprints, with single laser pulses, a complete identification code or three-dimensional pattern and leaves the surface in a state of deep residual compressive stress. A state of compressive stress in parts made of metal or other materials is highly desirable to make them resistant to fatigue failure and stress corrosion cracking. This process employs a laser peening system and beam spatial modulation hardware or imaging technology that can be setup to impress full three dimensional patterns into metal surfaces at the pulse rate of the laser, a rate that is at least an order of magnitude faster than competing marking technologies.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: The Regents of the University of California (Oakland, CA)
• Patent Number(s): US 6423935
• OSTI ID: 874614
• Country of Publication: United States
• Language: English

Related Subjects

identification
marking
means
laser
peening
method
apparatus
components
inducing
shock
wave
surface
results
indented
strained
layer
residual
compressive
stress
embodiment
peenmarking
rapidly
imprints
single
pulses
complete
code
three-dimensional
pattern
leaves
deep
metal
materials
highly
desirable
resistant
fatigue
failure
corrosion
cracking
process
employs
beam
spatial
modulation
hardware
imaging
technology
setup
impress
dimensional
patterns
surfaces
pulse
rate
magnitude
faster
competing
technologies
laser pulse
surface layer
compressive stress
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