Theses and Dissertations
ORCID
https://orcid.org/0009-0005-1996-5798
Issuing Body
Mississippi State University
Advisor
Rhee, Hongjoo
Committee Member
Mujahid, Shiraz
Committee Member
Paudel, YubRaj
Committee Member
Woody, Jon
Date of Degree
12-13-2024
Original embargo terms
Complete embargo 6 months
Document Type
Graduate Thesis - Open Access
Major
Mechanical Engineering
Degree Name
Master of Science (M.S.)
College
James Worth Bagley College of Engineering
Department
Michael W. Hall School of Mechanical Engineering
Abstract
The high-velocity impact of powder particles in cold-spray additively manufactured (CSAM) parts creates intersplat boundaries with regions of high dislocation densities and sub-grain structures. Upon microstructure and mechanical characterization, CSAM Aluminum 6061 showed non-uniformity, with spatial variation in the microstructure and mechanical properties affecting the overall response of the additively manufactured parts. Post-processing treatments are conducted in as-printed samples to improve particle bonding, relieve residual stresses, and improve mechanical properties. In this work, we attempt to implement the effects of grain size and distribution of smaller grains along the intersplat boundaries using the grain size distribution function and powder size information to accurately predict the deformation response of cold-sprayed material using a mean-field viscoplastic self-consistent (VPSC) model. The incorporation of an intersplat boundary term in the VPSC model resulted in a stress–strain response closely matching the experimental findings, preventing the superficially high stresses observed due to Hall–Petch effects from ultrafine- grain structures. Likewise, the results from the grain analysis showed the combined effects of grain size, orientation, and intersplat mechanisms that captured the stresses experienced and strain accommodated by individual grains.
Recommended Citation
Williams, Aulora Gail, "Crystal plasticity modeling to capture microstructural variations in cold-sprayed materials" (2024). Theses and Dissertations. 6352.
https://scholarsjunction.msstate.edu/td/6352