Scalable manufacturing of hierarchical nanostructures for thermal management
Author(s)Love, Christopher J., Ph.D. Massachusetts Institute of Technology
Massachusetts Institute of Technology. Dept. of Mechanical Engineering.
Kripa K. Varanasi.
MetadataShow full item record
The focus of this thesis is a new simple and scalable process to make surface coatings that have multiple length scales, or hierarchical features. Typically, the formation of hierarchical structures involves multiple steps and/or long processing times. In this new process, the hierarchical geometry is formed in a single step. The starting material-spherical copper powder-is oxidized in ambient air. Depending on the starting size of the powder, copper oxide nanowires may or may not form. Systematic thermogravimetric analysis (TGA) and in-situ x-ray diffraction (XRD) studies provide insights into the size-dependent thermal oxidation process. The proposed mechanism is supported by another interesting geometrical transformation: in the same single-step process, a large void is formed in the particles. The tunable nanowire growth is used to make new kinds of hierarchical coatings with enhanced heat-transfer performance in spray-cooling applications, which include nuclear reactor boiling, continuous casting of metals, and thermal management of electronics.
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 24-26).
DepartmentMassachusetts Institute of Technology. Department of Mechanical Engineering
Massachusetts Institute of Technology