John N. DuPont Research
Joining and welding are used by most major industries such as aircraft and aerospace, automotive, power generation, and electronics. Professor DuPont and his students are conducting research to understand the relationships between the processing, microstructure, and properties in joining and solidification. This work involves a combined experimental and modeling approach that relies heavily on microstructural and property characterization. Current research is sponsored by both industrial and government organizations to model and control the solidification behavior in complex alloys such as high alloy austenitic stainless steels and nickel base superalloys. The resultant properties of interest include, mechanical (e.g., toughness and fatigue crack growth), high temperature and aqueous corrosion, and solid particle erosion. Interdisciplinary research is also being conducted with the Mechanical Engineering Department to develop models for heat flow and residual stresses in welds, and with the Chemical Engineering Department for controlling welding fumes.
Light optical photomicrograph of martensite layer that forms along the fusion line of a dissimilar metal weld between ferritic steel and austenitic stainless steel.
Current Research Programs:
· Presidential Early Career Award for Scientists and Engineers, Interdisciplinary Research and Education in Solid Freeform Fabrication with Laser Engineered Net Shaping, National Science Foundation.
· The Influence of Gadolinium on the Microstructure of Nickel Base Alloys, Department of Energy Spent Nuclear Fuel Program, D.B. Williams, Co-PI.
· Young Investigator Award, Laser Welding and Surface Treatment of Super-Austenitic Stainless Steels for Advanced Double Hull Combatant Ships, Office of Naval Research.
· with Herman Nied and John Ochs of ME Department, Mikkel Groover of IE Department, Scott Hummel of ME Department Lafayette College, and Randall German of ME Department Penn State University, Co-PIs, Acquisition of a Solid Freeform Fabrication Laboratory for Interdisciplinary Research and Education in Manufacturing through a University/Industry Consortium, National Science Foundation.
· Fatigue Behavior of Austenitic Dissimilar Welds, A.R. Marder, Co-PI, Office of Naval Research.
· Corrosion, Fatigue, and Weldability of GTA Welds Prepared with Surface Active Fluxes, A.R. Marder, Co-PI, Office of Naval Research.
· Evaluation of the Susceptibility of AL-6XN Weldments to Localized Corrosion, with L.E. Friedersdorf (PI) and A.R. Marder (Co-PI), Office of Naval Research.
· Microstructural Analysis of Super Austenitic Stainless Steel Friction Stir Welds, Office of Naval Research.
· Large Scale Finite Element Modeling of Welding Residual Stresses and Distortion for Stainless Steel Advanced Double Hull Combatant Ships, with H.F. Nied, PI, Office of Naval Research.
· The Effect of Chromium on the Corrosion Resistance and Weldability of Fe-Al Weld Overlays, Department of Energy Fossil Energy Materials Program, June, A.R. Marder, PI.
· Sensitivity Analysis for Large Welded Structures, H.F. Nied, Co-PI, Mechanical Engineering and Mechanics, Lehigh University, and A.F. Noor, NASA Langley Research Center, submitted to Office of Naval Research.
· Corrosion Behavior of Friction stir Welds, Office of Naval Research, with A.R. Marder, PI, April, 2001.
· Remaining Life Assessment of Circumferentially Cracked Weld Overlay Coatings, with A.R. Marder (PI), consortium of power generation companies, September, 2000.
· Development of Low Cost Weld Overlay Coatings for Low Nox Waterwall Tubes, with A.R. Marder (PI), consortium of power generation companies, September, 2000.
·S. W. Banovic, J. N. DuPont, and A. R. Marder, "Dilution and Microsegregation in Dissimilar Metal Welds Between Super Austenitic Stainless Steels and Ni Base Alloys," Science & Technology of Welding and Joining 7, 1 (2002).