A Process Optimization Framework for Direct Energy Deposition: Densification, Microstructure, and Mechanical Properties of an Iron-Chromium Alloy /

Bibliographic Details
Main Author: Whitt, Austin (Author)
Other Authors: Karaman, Ibrahim (Thesis advisor)
Format: Thesis eBook
Language:English
Published: [College Station, Texas] : [Texas A&M University], [2023]
Subjects:
Online Access:Link to OAKTrust copy
Description
Abstract:Direct Energy Deposition (DED) is a metal additive manufacturing (AM) technique with the ability to fabricate compositional gradients through in-situ alloying. To fabricate functional gradients, it is necessary to understand what process parameters are suitable for printing the materials in the gradient. This study proposes a framework to optimize several critical process parameters: laser power, scan speed, mass flow rate, hatch spacing, and layer height. The framework utilizes single laser scans and geometric criteria to propose a range of process parameters likely to result in high-density parts. The proposed framework is validated by printing Fe-9wt.%Cr as a surrogate for radiation damage-resistant steels. These steels are of interest for functionally graded plasma-facing components in fusion reactors. Using the framework, high-density Fe-9wt.%Cr samples were fabricated using a variety of process parameters. The mechanical properties and microstructure of as-printed Fe-9wt.%Cr are characterized using tensile testing, microscopy, and X-ray diffraction. The electronic version of this dissertation is accessible from https://hdl.handle.net/1969.1/197260
Item Description:"Major Subject: Materials Science and Engineering"
Includes vita.
Physical Description:1 online resource.
Bibliography:Includes bibliographical references.