ICALEO 2010 Paper #407 (X-Ray Analysis of Pore Formation in Direct Metal Deposition and Its Causes)

X-Ray Analysis of Pore Formation in Direct Metal Deposition and Its Causes
Authors:
M Naveed Ahsan, Manufacturing and Management Group,The University of Manchester; Manchester Great Britain
Andrew J Pinkerton, Manufacturing and Management Group, the University of Manchester; Manchester Great Britain
Robert Bradley, Henry Moseley X-ray Imaging Facility, School of Materials, The University of Manchester; Manchester Great Britain
Presented at ICALEO 2010

Laser direct metal deposition has wide applications in the areas of rapid manufacturing, surface coating and
component repair. Defects of interlayer and intralayer porosity are often observed in laser deposited structure...

ICALEO 2010 Paper #408 (In-Situ Spectroscopic Analysis of Laser Induced Plasma for Monitoring of Composition during Direct Metal Deposition Process)

In-Situ Spectroscopic Analysis of Laser Induced Plasma for Monitoring of Composition during Direct Metal Deposition Process
Authors:
Lijun Song, Center for Laser Aided Intelligen Manufacturing, University of Michigan; Ann Arbor MI USA
Jyoti Maz, Center for Laser Aided Intelligen Manufacturing, University of Michigan; Ann Arbor MI USA
Presented at ICALEO 2010

Real time chromium and iron elemental analysis during a laser direct deposition process was carried out using optical emission spectroscopy. Mixtures of pure chromium powder and iron powder with different weight ratios were deposited onto a substrate by delivering the powder mixtures co-axially with a high power CO2 laser be...

ICALEO 2010 Paper #501 (Ultra High Speed Camera Investigations of Laser Beam Welding)

Ultra High Speed Camera Investigations of Laser Beam Welding
Authors:
Ingemar Eriksson, Luleå Univ of Techn; Lulea Sweden
John Powell, Luleå University of Technology; Luleå Sweden
Alexander Kaplan, Luleå Univ of Techn; Lulea
Presented at ICALEO 2010

With the help of high speed camera equipment, researchers can now directly observe melt flow phenomena which only could be imagined or simulated in the past. In this paper the motion of the molten metal inside the keyhole has been observed at frame rates as high as 180000 fps to provide useful information about the laser beam welding process. This paper describes two different cases where high speed imaging has given n...

ICALEO 2010 Paper #502 (Influencing the Melt Pool Dynamics with Short Pulses)

Influencing the Melt Pool Dynamics with Short Pulses
Authors:
Rudolf Weber, Institut Strahlwerkzeuge IFSW, Universität Stuttgart; Stuttgart Germany
Roland Gauch, Institut Strahlwerkzeuge IFSW, Universität Stuttgart; Stuttgart Germany
Thomas Graf, Institut Strahlwerkzeuge IFSW, Universität Stuttgart; Stuttgart Germany
Presented at ICALEO 2010

The details of the melt flow dynamics in deep penetration welding as well as in laser cutting are still not completely understood. In addition, control of the melt flow might help to suppress or eliminate defects such as spattering, humping or dross formation.

The present paper describes the use of a short pulse laser to infl...

ICALEO 2010 Paper #503 (Novel High-Speed Space-Resolved X-Ray System for In-Situ Diagnostics of Laser Based Processes)

Novel High-Speed Space-Resolved X-Ray System for In-Situ Diagnostics of Laser Based Processes
Authors:
Felix Abt, Ifsw, Institut Fur Strahlwerkzeuge; Stuttgart Germany
Rudolf Weber, Ifsw, Institut Fuer Strahlwerkzeuge; Stuttgart Germany
Thomas Graf, Ifsw, Institut Fuer Strahlwerkzeuge; Stuttgart Germany
Presented at ICALEO 2010

The comprehensive diagnostics of melt pool and keyhole dynamics is crucial in the ambitious efforts of understanding the complex behaviour of laser welding and cutting processes. A major drawback for the in-situ diagnostics of laser based processes is the fact that high-speed cameras and other optical sensors are only showing phenomena on the su...

ICALEO 2010 Paper #504 (Studies in the Interpretation of the Reflected Feedback from Laser Welding)

Studies in the Interpretation of the Reflected Feedback from Laser Welding
Authors:
R. Olsson, Laser Nova AB; Stersund Sweden
I. Eriksson, Luleå University of Technology; Luleå Sweden
J. Powell, Luleå University of Technology; Luleå Sweden
A.V. Langtry, GE Healthcare; Nottingham Great Britain
A.F.H. Kaplan, Luleå University of Technology; Luleå Sweden
Presented at ICALEO 2010

This paper investigates two methods of monitoring the laser welding
process by statistical analysis of the reflected laser light signal.
It has been discovered that real-time data manipulation reveals more
about pertubations in the welding process than the s...

ICALEO 2010 Paper #505 (Influence on the Efficiency of the Heat Conduction Mode Laser Beam Welding Process Regarding Different Laser Spot Geometries)

Influence on the Efficiency of the Heat Conduction Mode Laser Beam Welding Process Regarding Different Laser Spot Geometries
Authors:
Rüediger Daub, Technische Universität Műnchen. Institute for Machine Tools and Industrial Management; Garching Germany
Robert Wiedenmann, Technische Universität Műnchen. Institute for Machine Tools and Industrial Management; Garching Germany
Achim Mahrle, University of Technology Dresden, Institute for Surface and Production Technology; Dresden Germany
Jeudi Duong, Lappeenranta University of Technology; LUT Metals Finland
Michael F. Zaeh, Technische Universität Műnchen. Institute for Machine Tools and Industrial Management...

ICALEO 2010 Paper #506 (Interaction Time Effects on the Transition Between Conduction and Keyhole Laser Welding)

Interaction Time Effects on the Transition Between Conduction and Keyhole Laser Welding
Authors:
Eurico Assuncao, Welding Engineering Research Centre, Cranfield University; Cranfield Great Britain
Stewart Williams, Welding Engineering Research Centre, Cranfield University; -
David Yapp, Welding Engineering Research Centre, Cranfield University; -
Presented at ICALEO 2010

Welding with a laser in keyhole mode provides deep penetration and/or high process speeds. On the other hand welding in the conduction provides much higher quality with no defects or spatter. When welding in conduction mode it is essentially to avoid keyhole effect in order to maintain this quality. ...

ICALEO 2010 Paper #507 (Laser Power Modulation at the Threshold from Heat Conduction to Deep-Penetration Welding)

Laser Power Modulation at the Threshold from Heat Conduction to Deep-Penetration Welding
Authors:
Peter Stritt, GSaME Graduate School of Excellence advanced Manufacturing Engineering; Stuttgart Germany
Rudolf Weber, Ifsw Institut Fuer Strahlwerkzeuge; Stuttgart Germany
Thomas Graf, Ifsw Institut Fuer Strahlwerkzeuge; Stuttgart Germany
Steffen Mueller, Audi AG; Neckarsulm Germany
Christian Ebert, Audi AG; Neckarsulm Germany
Presented at ICALEO 2010

Today, lasers are operated either in pulsed or cw (continuous wave) mode for laser welding applications. While the cw mode is common for larger structural welds, pulsed welding is mainly used for sma...

ICALEO 2010 Paper #509 (Hot Cracking by High Power Laser Beam Welding of Thick High Strength Structural Steels Under Restraint Conditions)

Hot Cracking by High Power Laser Beam Welding of Thick High Strength Structural Steels Under Restraint Conditions
Authors:
Vanessa Quiroz, BAM Federal Institute for Materials Research and Testing; Berlin Germany
Moritz Gebhardt, BAM Federal Institute for Materials Research and Testing; Berlin Germany
Sergej Gook, BAM Federal Institute for Materials Research and Testing; Berlin Germany
Andrey Gumenyuk, BAM Federal Institute for Materials Research and Testing; Berlin Germany
Michael Rethmeier, BAM Federal Institute for Materials Research and Testing; Berlin Germany
Presented at ICALEO 2010

High power laser beam welding represents a cost-effectiv...