Nathan Klingbeil, Ph.D. (Advisor); Daniel Young, Ph.D. (Committee Member); Ryan Kemnitz, Ph.D. (Committee Member)
Master of Science in Mechanical Engineering (MSME)
Refractory metal alloys in the tungsten molybdenum rhenium ternary system were additively manufactured using laser power bed fusion. Four ternary alloys with varying concentrations of tungsten, molybdenum, and rhenium were manufactured and manufactured again with an addition of 1 wt% hafnium carbide. Samples were heat treated to heal cracks, reduce porosity, and reduce inhomogeneity. Material microstructure was characterized before and after heat treatment using microscopy, energy dispersive x-ray spectroscopy, and electron backscatter diffraction mapping. Mechanical testing was conducted on both three-point bend specimens and compression specimens, resulting in maximum bending strengths of 677.86 MPa, and maximum compression 0.2% yield strengths of 583.88 MPa for the strongest composition. The ternary alloy samples exhibited less porosity, less cracking, more refined grains, and higher strengths. The hafnium carbide doped samples exhibited more cracking and porosity, larger grains, and lower overall strengths.
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
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