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Search Publications by: Tim Quinn (Fed)

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Displaying 26 - 36 of 36

A Coupled Arc and Droplet Model of GMAW

January 8, 2005
Author(s)
Timothy P. Quinn, M Szanto, T Gilad, I Shai
A model of gas metal arc welding was developed that solves the magneto-hydrodynamic equations for the flow and temperature fields of the molten electrode and the plasma simultaneously, to form a fully coupled model. A commercial finite element code was

Constitutive Models for a Poly(e-caprolactone) Scaffold

October 1, 2004
Author(s)
Timothy P. Quinn, Tammy L. Oreskovic, Christopher N. McCowan, N Washburn
We investigate material models for a porous, polymeric scaffold used for bone. The material was made by co-extruding poly (e-caprolactone) (PCL), a biodegradable polyester, and poly(ethylene oxide)(PEO). The water soluble PEO was removed resulting in a

A Mathematical Model of Wire Feeding Mechanisms in GMAW

July 1, 2003
Author(s)
T M. Padilla, D. R. Munoz, Timothy P. Quinn, R. A. Rorrer
A Hertzian based contact model of the friction between the welding wire and the wire liner has been developed to predict the wire pulling force for gas metal arc welding (GMAW). The model predicts a 2.5:1exponential increase in wire pulling force as the

GMAW Wire Feedability: A Friction Model

July 1, 2003
Author(s)
A Padilla, D. R. Munoz, Timothy P. Quinn, R. A. Rorrer
A Hertzian-based contact model of the friction between the welding wire and the wire liner has been developed to predict the wire pulling force for gas metal arc welding (GMAW). The model predicts a 2.5:1 exponential increase inwire pulling force as the

An Experimental Method for Measuring Mechanical Properties of Rat Pulmonary Arteries Verified With Latex

June 1, 2003
Author(s)
Elizabeth S. Drexler, Andrew J. Slifka, J Wright, Christopher N. McCowan, Dudley Finch, Timothy P. Quinn, J D. McCloskey, Dunbar Ivy, Robin Shandas
A study of the biomechanics and hemodynamics of pulmonary hypertension is incomplete without including mechanical properties data comparing healthy and diseased arterial tissue. In the initial stabe of this study, Sprague-Dawley rats will be induced with

XML for Exchange of Weld Inspection Results

April 1, 2003
Author(s)
William G. Rippey, Timothy P. Quinn, John L. Michaloski
TECHNICAL SUMMARYIntroduction/Background SectionA system to demonstrate the transfer of weld inspection data between computer programs is described in this paper. The goal is effortless flow of the data between multi-vendor welding software applications

Process Sensitivity of GMAW: Aluminum vs. Steel

April 1, 2002
Author(s)
Timothy P. Quinn
A heat-transfer model of the melting electrode in gas metal are welding (GMAW) was used to compare the relative sensitivity of the process when welding with aluminum electrodes compared to that of steel electrodes. The aluminum model was verified with

Contact Tube Temperature During GMAW

December 1, 2001
Author(s)
G Adam, Thomas A. Siewert, Timothy P. Quinn, D P. Vigliotti
The rate of heating and the maximum temperature reached by the contact tube during gas metal arc welding (GMAW) is quantified. We studied the effect of changes in the contact-tube-to-work distance (CTWD), voltage, welding wire feed speed, gas flow rate

A Welding Cell With Its Own Web Site

January 1, 2000
Author(s)
Timothy P. Quinn
Communications technology is allowing welding engineers to interact in the operation of a welding cell from a distance, as if they were physically present. The remote engineer can look at the weld, watch the robot motion, read front panel displays and

A Welding Cell That Supports Remote Collaboration

September 30, 1999
Author(s)
James D. Gilsinn, William G. Rippey, Joseph A. Falco, Timothy P. Quinn, Robert Russell, Keith A. Stouffer
Discrete part manufacturers using robotic arc welding cells often have several more geographically distributed plants than welding experts. This ratio often leads to costly downtimes due to both logistic and communication deficiencies between weld

Through-the-Arc Detection of Weld Defects in Pulsed GTAW

March 1, 1998
Author(s)
Timothy P. Quinn, D C. Oakley
A through-the-arc sensing system was used to detect defects in the welding of thin-walled stainless-steel tubing. It measures the process current and voltage and passes the resulting signals through a signal processing algorithm. The arc condition number