| About this Abstract |
| Meeting |
2024 AWS Professional Program
|
| Symposium
|
2024 AWS Professional Program
|
| Presentation Title |
Characterization of Composition Gradients Deposited by Multi-wire Gas Tungsten Arc Directed Energy Deposition |
| Author(s) |
Tate Patterson, Michael Glazoff, Joel Simpson, Denis Clark, Thomas Lillo |
| On-Site Speaker (Planned) |
Tate Patterson |
| Abstract Scope |
Advancement of manufacturing methods and metallic alloys is critical for developing next generation energy production systems to operate with higher efficiencies and longer operating lifetimes. One approach for optimizing component properties is via additive manufacturing (AM) techniques. Wire-based AM methods are being pursued for larger-scale components, where intricate features are not a necessity, wire metals are often cheaper than powdered metal, and deposition rates are higher than powder-based AM methods.
To further expand the capabilities of wire arc additive manufacturing, a multi-wire gas tungsten arc directed energy deposition (GTA-DED) system was developed that can independently introduce three weld wires into a single weld pool. Using this system, it is possible to expand metallic alloy selections and optimize material properties and/or weldability performance with commercially available weld wire. Additionally, it is possible to selectively grade chemical composition to avoid abrupt changes in material properties that can reduce joint/component performance. However, wire feed rate step-changes will likely be unavoidable during the deposition of a continuously graded structure.
This research demonstrated that multi-wire DED-GTA can deposit defect-free, graded compositions during wire feedstock step-changes using nickel alloys. Additionally, it analyzed the composition profiles that result from step-changes in the wire feedstock for two levels of heat input to begin to understand the influences of deposition parameters and conditions on the resulting composition profiles. The substrate was Alloy 617, and the two filler metals were Alloy 617 and Alloy 740H. The total volumetric feed rate of both wires was kept constant while changing the relative feed rates of each wire feedstock. Analysis was performed for five weld regions and for four step-changes in weld wire feed rates. Optical microscopy showed weld metal dilution at each region, and energy dispersive spectroscopy was used to analyze the composition across each wire feed rate step-change. |
| Proceedings Inclusion? |
Undecided |