Real-time ultrasonic sensing of arc welding processes

Lott, L. A.; Johnson, John A.; Smartt, H.B.

doi:10.2172/6810314

Cited by 13 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The feasibility work on detecting the molten weld pool started in 1977 [3]. Water was used as the coupling medium between the transducer and a 25.4 mm steel welding sample, which was only partially immersed in water to allow welding on upper surface.…”

Section: Previous Workmentioning

confidence: 99%

Ultrasonic Detection of Weld Bead Geometry

Carlson

Johnson

1987

Review of Progress in Quantitative Nondestructive Evaluation

View full text Add to dashboard Cite

Section: Previous Workmentioning

confidence: 99%

Ultrasonic Detection of Weld Bead Geometry

Carlson

Johnson

1987

Review of Progress in Quantitative Nondestructive Evaluation

View full text Add to dashboard Cite

“…International Complex Sulfides Symposium-Processing of Ores, Concentrates, and By-Products November [10][11][12][13]1985 San Diego, California…”

Section: Tms·aime Extractive and Process Metallurgy Fall Meetingmentioning

confidence: 99%

Meetings Calendar

1985

JOM

View full text Add to dashboard Cite

Toronto, CanadaThis annual forum, held in conjunction with ASM Metals Congress, addresses the latest developments in physical and mechanical metallurgy. General abstract sessions and TMS-AIME committee-sponsored sessions will be featured.For further information, contact Meetings Department, TMS-AIME Headquarters, 420 Commonwealth Drive, Warrendale, Pennsylvania 15086; telephone (412) 776-9050. Aluminum Powder MetallurgySponsors: TMS-AIME Powder Metallurgy and Composites Committees Four-session symposium on High-Strength Powder Metallurgy Aluminum Alloys-II will provide a forum for presentation and current research on processing, properties, microstructure, and applications of full-density aluminum powder metallurgy alloys. Sessions will be organized to cover fundamental and applied research on high-strength heattreatable, dispersion-strengthened, wearresistant, low-density, and particulate/ short fiber metal matrix composite aluminum powder metallurgy alloys.Submit abstracts up to 150 words by April 1, 1985 to Gregory J. Hildeman,

show abstract

“…The purpose of the ultrasonic sensor is to detect defects in the solidified weld metal on a pass-by-pass basis [2][3][4][5] for a multipass, pulsed gas metal arc welding (GMA W) process. The sensor is being developed under the Programmable Automated Welding System (PAWS) project.…”

Section: Introductionmentioning

confidence: 99%

“…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.The purpose of the ultrasonic sensor is to detect defects in the solidified weld metal on a pass-by-pass basis [2][3][4][5] for a multipass, pulsed gas metal arc welding (GMA W) process. The sensor is being developed under the Programmable Automated Welding System (PAWS) project.…”

mentioning

confidence: 99%

Noncontacting Ultrasonic System for Concurrent Defect Detection in Solidified Weld Metal

Carlson

Johnson

Larsen

1993

Review of Progress in Quantitative Nondestructive Evaluation

View full text Add to dashboard Cite

INTRODUCTIONIn-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, an electromagnetic acoustic transducer (EMAT) for ultrasound reception, and a PC-based data acquisition system which determine 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 [5]. 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.The purpose of the ultrasonic sensor is to detect defects in the solidified weld metal on a pass-by-pass basis [2][3][4][5] for a multipass, pulsed gas metal arc welding (GMA W) process. The sensor is being developed under the Programmable Automated Welding System (PAWS) project. The purpose of the PAWS program is to demonstrate the integration of the latest welding technology into a single system. The PAWS system consists of a central control computer, an off-line programmer for planning, and eight different sensors. This paper discusses one of those sensors. The sensor system will be demonstrated on thick section (31.8 to 41.3 mm, 1.25 to 1.625 in.) steel weld samples.The ultrasound is generated by a short duration (11 ns) light pulse from an Nd:YAG laser with an exit beam power of 56 mJ/pulse. The 1 mm laser spot is delivered at a 20 Hz rate to the solidified top surface of the weld several inches behind the electrode using focusing optics mounted on the laser head [6,7]. The ultrasonic detector is an EMA T and amplifier designed and fabricated for PAWS at the National Institute of Standards and Technology in Boulder, Colorado [8]. The permanent magnet EMAT generates a magnetic field in the weld sample. The motion of electrons due to the sound generated by the laser pulse interacts with the magnetic field, changing an associated electrical field. This interaction is detected by a pickup coil. The signal is then evaluated as an ultrasonic A scan. The ultrasonic system includes the hardware and software necessary to monitor the condition of the solidified weld metal while receiving and sending information to a weld controller about the quality of the solidified weld bead. A first step in devising a noncontacting technique for sensing defect generation in the welding process is to develop a method for generating sound waves in the material. In this system, ultrasound is generated by a focused, 1 mm (0.039 in.) diameter laser spot from a pulsed Nd: Y AG laser operating at 1064 nm. The short duration, 11 ns, laser pulse has a peak intensity of 107 W/cm2 and generates high freq...

show abstract

Real-time ultrasonic sensing of arc welding processes

Abstract: This report was prepared as an account of work sponsored by an agency of the United States Government.

Cited by 13 publications

References 0 publications

Ultrasonic Detection of Weld Bead Geometry

Ultrasonic Detection of Weld Bead Geometry

Meetings Calendar

Noncontacting Ultrasonic System for Concurrent Defect Detection in Solidified Weld Metal

Contact Info

Product

Resources

About