Investigation of nanopowder laser sintering for additive manufacturing of thermoelectric devices

Authors
Hoffman, Dustin
ORCID
Loading...
Thumbnail Image
Other Contributors
Borca-Tasçiuc, Theodorian
Oehlschlaeger, Matthew A.
Anderson, Kurt S.
Issue Date
2016-05
Keywords
Mechanical engineering
Degree
MS
Terms of Use
This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
Full Citation
Abstract
A beam of green light (532nm wavelength) produced by a 500mW diode-pumped solid-state laser was focused onto bismuth telluride nanopowder on glass substrates. Powder layers were deposited via spray-coating of colloidal dispersions of bismuth telluride in ethanol and methanol. Scans were made with 250, 325, and 400mW beam power at scan velocities of 0.02, 0.08, 0.14, and 0.20mm/s. Consolidated samples were analyzed with optical microscopy and surface profilometry. Trends in the data indicate an inverse relationship between line widths and scan velocity, a proportional relationship between line thicknesses and scan velocity, and an increase in surface roughness with increasing velocity. Beam power relationships are less definitive, but increasing beam power leads to increased line width, as well as decreased thickness and roughness, indicative of increased densification. The experimental process highlighted above produces better repeatability than earlier attempts and considerations for future improvements are discussed.
Description
May 2016
School of Engineering
Department
Dept. of Mechanical, Aerospace, and Nuclear Engineering
Publisher
Rensselaer Polytechnic Institute, Troy, NY
Relationships
Rensselaer Theses and Dissertations Online Collection
Access
Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.