Ultrasound generation through a fiber optic delivery system using pulsed laser energy

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6426353

Carlson, N M; Johnson, J A

Short duration laser pulses can generate high frequency, broadband ultrasound in a material without contacting the surface. For these noncontacting techniques to be useful on the shop floor, in remote applications, and in harsh environments, a dependable delivery system must be developed. Fiber optic techniques have been used to deliver either moderate laser energy for a large number of pulses or a large laser energy for a few pulses for the purpose of generating acoustic waves. However, transmitting high energy pulses continuously through a fiber is required for practical sensing systems. Fiber optics systems are currently used for a long duration pulses (of the order of milliseconds) in laser welding applications; e.g. a welding systems developed for manufacture of headlamps uses a fiber optic delivery system. The key to the success of this welding systems is the coupling technique used to deliver laser power to the fiber. Because the pulse duration is on the order of several milliseconds, the power density in the fiber is several orders of magnitude below the power densities required for ultrasonic applications. 17 refs., 2 figs.

• Research Organization: EG and G Idaho, Inc., Idaho Falls, ID (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC07-76ID01570
• OSTI ID: 6426353
• Report Number(s): EGG-M-90086; CONF-900791--7; ON: DE91001914
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420200 -- Engineering-- Facilities
Equipment
& Techniques
420500 -- Engineering-- Materials Testing
440600* -- Optical Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
ALLOYS
BEAMS
DAMAGE
FABRICATION
FIBER OPTICS
FIBERS
IRON ALLOYS
IRON BASE ALLOYS
JOINING
LASER WELDING
LASERS
NEODYMIUM LASERS
OPTICAL FIBERS
PULSES
RAYLEIGH WAVES
RUBY LASERS
SEISMIC SURFACE WAVES
SEISMIC WAVES
SOLID STATE LASERS
SOUND WAVES
STEELS
TESTING
TRANSMISSION
ULTRASONIC WAVES
WAVELENGTHS
WELDING