Publication Date
2025
Document Type
Thesis
Committee Members
Henry D. Young, Ph.D. (Advisor); Ashan Mian, Ph.D. (Committee Member); Raghavan Srinivasan, Ph.D. (Committee Member)
Degree Name
Master of Science in Materials Science and Engineering (MSMSE)
Abstract
We studied the additive manufacturing of an alumina-matrix composite reinforced with alumina fibers using the Admatec Admaflex 3D printer, which utilizes digital light processing technology. Oxide-oxide composites are composite materials in which both the matrix and the reinforcing element are ceramic oxides. Monolithic alumina ceramic exhibits a good combination of thermal and mechanical properties, including thermal shock resistance, high melting point, thermal oxidation resistance, good thermal conductivity, hardness, and mechanical strength. However, it is very brittle. Introducing alumina fiber as a reinforcing material into the alumina matrix is expected to enhance mechanical properties, particularly toughness, making the ceramic matrix composite suitable for use in harsh thermal environments. This work examined the impact of fiber load on the rheology of alumina slurry and its printability under shear stress. The effects of fiber load on cure depth and surface roughness of single layers were studied. Testing bars with different proportions of alumina fiber load were printed and sintered after the thermal debinding process. Samples were prepared, mounted, and characterized using a scanning electron microscope. The microstructure was analyzed to evaluate the interaction between the matrix and fibers. Fiber pullout and microscale delamination were observed. Densification of the fiber-loaded testing bars was characterized, and a four-point bending test was conducted to quantify flexural strength and toughness modulus. The trade-off between printability on the Admatec Admaflex printer and mechanical properties was studied; high fiber load impairs densification and mechanical properties.
Page Count
96
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
2025
Copyright
Copyright 2025, all rights reserved. My ETD will be available under the "Fair Use" terms of copyright law.
ORCID ID
0009-0005-8745-3145
