Identification marking by means of laser peening
US6423935B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 2000 |
| Grant date | Jul 23, 2002 |
| Priority date | — |
| Expiry date | Jul 31, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K2019/06271
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.