Application of laser speckle strain measurement to weld monitoring

Journal Article · Sun May 01 04:00:00 EDT 1994 · Welding Journal (Miami); (United States)

OSTI ID:7303410

Muramatsu, Yoshiki; Kuroda, Seiji ^[1]

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1. National Research Institute for Metals, Tokyo (Japan)

The laser speckle method has been applied to the measurement of dynamic strains at high temperature in welding. The method depends on the fact that the speckle pattern formed by the scattered light from an object surface under laser illumination deforms with a specific relation to the surface strains on the object. The strains on the bottom surface of a steel plate were measured by the speckle method while a GTA traversed on top of it. Qualitatively reasonable strain behavior was observed except for a period when the arc was in the vicinity of the measuring point. In order to understand the reasons behind the problem, simple model experiments were carried out to see the effects of strains and rigid body motions on the speckle patterns. The results indicate that a high rate of strain change as well as some components of the rigid body motions of the specimen are likely to be the causes of the difficulty.

• OSTI ID: 7303410
• Journal Information: Welding Journal (Miami); (United States), Journal Name: Welding Journal (Miami); (United States) Vol. 73:5; ISSN 0043-2296; ISSN WEJUA3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
42 ENGINEERING
420500 -- Engineering-- Materials Testing
ALLOYS
ARC WELDING
ELECTROMAGNETIC RADIATION
FABRICATION
GAS METAL-ARC WELDING
GAS TUNGSTEN-ARC WELDING
IRON ALLOYS
IRON BASE ALLOYS
JOINING
LASER RADIATION
MEASURING METHODS
MONITORING
RADIATIONS
STEELS
STRESSES
THERMAL STRESSES
WELDING