Solidification dynamics in a binary alloy systems

dc.contributor.author Eshelman, Mark
dc.contributor.department Materials Science and Engineering
dc.date 2018-08-17T07:42:11.000
dc.date.accessioned 2020-07-02T06:07:31Z
dc.date.available 2020-07-02T06:07:31Z
dc.date.copyright Thu Jan 01 00:00:00 UTC 1987
dc.date.issued 1987
dc.description.abstract <p>Quantitative directional solidification experiments have been carried out in transparent metal analog systems to examine linear and nonlinear theories of planar interface instability, to track the pattern formation process, to examine steady-state and dynamical processes in the cellular growth region, and to examine the effects of anisotropy of interface properties on growth morphologies. Studies of planar interface instability show that the linear theory of stability accurately describes the critical conditions for the planar interface instability, but it does not accurately describe the wavelengths observed. The nonlinear theory of planar interface instability predicts the possibility of subcritical bifurcation, which was experimentally observed here;Studies of pattern formation show that the pattern formation process is not entirely caotic, but rather, a discrete set of transition wavenumbers exist during the pattern formation process;Studies in the cellular growth region show that the steady-state cellular spacing decreases, increases sharply, and again decreases as the velocity is increased from the point of planar interface instability to the maximum cell growth velocity. Dynamic experiments in the cellular growth region show that adjustment of the cell spacing requires drastic growth morphology changes when the growth conditions are changed slowly in systems where anisotropy of interface properties are present;Studies of the effects of anisotropy on solidification morphologies show that anisotropic interface properties cause cell translation parallel to an advancing solid-liquid interface when the 001 crystallographic direction is not in line with the heat flow direction.</p>
dc.format.mimetype application/pdf
dc.identifier archive/lib.dr.iastate.edu/rtd/8533/
dc.identifier.articleid 9532
dc.identifier.contextkey 6335291
dc.identifier.doi https://doi.org/10.31274/rtd-180813-13098
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath rtd/8533
dc.identifier.uri https://dr.lib.iastate.edu/handle/20.500.12876/81532
dc.language.iso en
dc.source.bitstream archive/lib.dr.iastate.edu/rtd/8533/r_8716763.pdf|||Sat Jan 15 02:13:08 UTC 2022
dc.subject.disciplines Metallurgy
dc.subject.keywords Materials science and engineering
dc.subject.keywords Metallurgy
dc.title Solidification dynamics in a binary alloy systems
dc.type article
dc.type.genre dissertation
dspace.entity.type Publication
relation.isOrgUnitOfPublication bf9f7e3e-25bd-44d3-b49c-ed98372dee5e
thesis.degree.level dissertation
thesis.degree.name Doctor of Philosophy
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