Date of Final Oral Examination (Defense)
Type of Culminating Activity
Master of Science in Materials Science and Engineering
Materials Science and Engineering
Brian J. Jaques, Ph.D.
Mike Hurley, Ph.D.
Amy J. Moll, Ph.D.
Ceramic to metal interfaces are of interest for applications in extreme environments because they allow increased operational temperatures, resulting in greater thermodynamic efficiency in energy conversion processes. Ceramics offer high temperature corrosion resistance while metals offer robust and versatile solutions to assemblies. Understanding the solid-state reactions, the resulting interfacial microstructure, and the properties of the joints produced by diffusion bonding is essential for developing reliable ceramic to metal interfaces.
The combination of silicon carbide (SiC) and a nickel-based alloy (Inconel 600) offers improved strength and resistance to high temperature degradation. This work focuses on the understanding of the solid-state diffusion reactions at the interface between SiC and Inconel 600 using a Ag or Ag-Pd interlayer. The diffusion bonding experiments were performed with several process parameters, including temperature (900-930 °C), uniaxial pressure (1-10 MPa), and bonding time (30-180 min). The effects of the process parameters on diffusion behavior and interfacial microstructure were investigated through scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and mechanical testing. In most cases, brittle interfacial solid-state reaction phases of Ni, Cr, and Pd-silicides were formed and affected the interfacial microstructure. The thickness of the reacted layer was used to determine that the diffusion mechanism for both interlayer systems followed parabolic kinetics, which is indicative that the process is diffusion-controlled. The precise control of diffusion reactions through bonding parameters is necessary to ensure the integrity and performance of the diffusion bonded SiC-Inconel 600 transitions.
Rodriguez Ortego, Yaiza, "Diffusion Bonding of Inconel 600 to Silicon Carbide for Next Generation High Temperature Applications" (2020). Boise State University Theses and Dissertations. 1683.