Ultrasonic sensing of GMAW: Laser/EMAT defect detection system. [Gas Metal Arc Welding (GMAW), Electromagnetic acoustic transducer (EMAT)]

Conference · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7237450

Carlson, N M; Johnson, J A; Larsen, E D ^[1]; Van Clark, A Jr; Schaps, S R; Fortunko, C M ^[2]

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1. EG and G Idaho, Inc., Idaho Falls, ID (United States)
2. National Inst. of Standards and Technology, Boulder, CO (United States)

In-process ultrasonic sensing of welding allows detection of weld defects in real time. A noncontacting ultrasonic system is being developed to operate in a production environment. The principal components are a pulsed laser for ultrasound generation and an electromagnetic acoustic transducer (EMAT) for ultrasound reception. A PC-based data acquisition system determines the quality of the weld on a pass-by-pass basis. The laser/EMAT system interrogates the area in the weld volume where defects are most likely to occur. This area of interest is identified by computer calculations on a pass-by-pass basis using weld planning information provided by the off-line programmer. The absence of a signal above the threshold level in the computer-calculated time interval indicates a disruption of the sound path by a defect. The ultrasonic sensor system then provides an input signal to the weld controller about the defect condition. 8 refs.

• Research Organization: EG and G Idaho, Inc., Idaho Falls, ID (United States)
• Sponsoring Organization: DOD; Department of Defense, Washington, DC (United States)
• DOE Contract Number: AC07-76ID01570
• OSTI ID: 7237450
• Report Number(s): EGG-M-92287; CONF-9206173--8; ON: DE92017916
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101 -- Metals & Alloys-- Preparation & Fabrication
42 ENGINEERING
420200* -- Engineering-- Facilities
Equipment
& Techniques
ARC WELDING
CHEMICAL ANALYSIS
COMPUTERIZED CONTROL SYSTEMS
COMPUTERS
CONTROL SYSTEMS
DATA ACQUISITION SYSTEMS
DEFECTS
DETECTION
DIGITAL COMPUTERS
FABRICATION
FEEDBACK
GAS METAL-ARC WELDING
JOINING
JOINTS
MICROCOMPUTERS
MONITORING
NONDESTRUCTIVE ANALYSIS
ON-LINE CONTROL SYSTEMS
ON-LINE SYSTEMS
PERSONAL COMPUTERS
TRANSDUCERS
ULTRASONOGRAPHY
WELDED JOINTS
WELDING