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A study of slip line lengths in aluminum single crystals during transient deformationDe Larios, John Martin January 1973 (has links)
Slip line length measurements have been carried out on oriented single crystals of high purity aluminum to qualitatively check the predictions of a new theory of plastic flow in strain hardened metals. This theory states that the slip line length L will be a function of the stress, σ, the yield strength, Ty, and the magnitude of the variation in the obstacle spacing, Tv.
To achieve this purpose, the specimens were prestrained at room temperature to the same stress level insuring that they had the same structure. They were then electropolished and given a small increment of strain at a temperature between 298°K and 4°K or a strain rate from ɛ = 1x10⁻⁴ /min to ɛ = 2x10⁻¹ /min. The slip line lengths for these increments were found to increase with increasing strain rate and to decrease
with increasing temperature, in agreement with the theory.
By applying the increment of strain in small, divisions, the slip line length was found to increase during the region of transient deformation following a quench. This increase in L was due to an increase in stress.
Lowering the prestrain temperature showed that the slip line length depended on the structure parameter Tv. A low temperature prestrain
resulted in a smaller Tv and therefore shorter slip lines.
From the 4°K increment, the parameters characterizing the prestrained structure and the structure after the increment could be determined. Using equations of the theory, these values were related to the experimental slip line length data with good quantitative agreement. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
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Dislocation substructure in quenched aluminum single crystalsStrudel, J. L. January 1963 (has links)
Thesis (Master's)--University of California, Berkeley, 1963. / "UC-25, Metals, Ceramics and Materials" -t.p. "TID-4500 (19th Ed.)" -t.p. Includes bibliographical references (p. 18-19).
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X-ray diffraction measurement of the change in the lattice parameter of high-purity aluminum during annealingEubig, Casimir, 1940- January 1965 (has links)
No description available.
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Deformation of aluminum alloy single crystalsLalwaney, Narain Shamdas, January 1966 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1966. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Preparation of high-purity aluminum bicrystalsEvans, Herbert Elgin, 1962- January 1989 (has links)
The preparation of bicrystal specimens of high interfacial purity and accurately controlled mismatch of orientation between grains with a specific boundary orientation are critical for fundamental studies of the structure and properties of grain boundaries. A method was developed for routinely producing high-purity aluminum bicrystals of desired mismatch and boundary orientation. A strain annealing technique was used for making large single crystals. The orientation, structural perfection, and chemical purity of the seeds were characterized, then the seeds were joined by using an electron beam welder. The welder was designed and built as a major portion of this work.
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Methods for calculating rates of transitions with application to catalysis and crystal growth /Henkelman, Graeme, January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (p. 129-136).
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