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Showing 1 to 15 of 15 for “"Macrosegregation"”.
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Macrosegregation.
Massachusetts Institute of Technology. Dept. of Metallurgy. Thesis. 1966. Sc.D.
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Macrosegregation in electroslag remelted ingots
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1978.
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Computer simulation of macrosegregation in ESR ingots
Thesis: M.S., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 1977
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Fluid Flow, Heat Flow and Macrosegregation in Axi-Symmetric Ingots
… to the interdendritic fluid flow responsible for macrosegregation in the "mushy" zone of ingots solidifying under axi-symmetric conditions. Experiments on both a low-temperature simulated ESR apparatus and on a 200mm ESR ingot mold verify the solidification model.
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Experimental observations and analysis of macrosegregation in rolling slab ingots
The increased demand for aluminum as a primary structural metal stems from a quest in automotive, aerospace, and marine industries to be more energy efficient and sustainable. This unprecedented demand drives aluminum casting methods towards increased productivity looking to, cast larger ingots …
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Containerless measurement and thermodynamic prediction of the physical properties of liquid steels
Incomplete control over macrosegregation during steel solidification hinders the development of novel steel alloys and applications by limiting compositions which can be successfully cast. Analysis of macrosegregation at the solidification front is aided by study of the liquid state via fluid …
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Detection of Floating Grains in DC Aluminum Casting
Free-moving "floating" grains have been linked to macrosegregation in direct-chill (DC) aluminum castings. The presence of these grains in the sump of a solidifying ingot has been acknowledged based on measurements of cast microstructures and by recent work using a turbulent jet to suspend …
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Modeling fluid interactions with the rigid mush in alloy solidification
<p>Macrosegregation is a casting defect characterized by long range composition differences on the length scale of the ingot. These variations in local composition can lead to the development of unwanted phases that are detrimental to mechanical properties. Unlike microsegregation, in which …
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A Study of Solidification With a Rotating Magnetic Field
… numerical model. The numerical model predicts macrosegregation effects similar to those observed in the experiments. The temperature traces obtained from experiments and predicted by the numerical calculations also agree very well. We extend the numerical framework to make microstructural …
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Modeling transport phenomena and uncertainty quantification in solidification processes
… quantified the uncertainty and sensitivity in macrosegregation, solidification time, and sump profile predictions. Uncertain model inputs of interest included the secondary dendrite arm spacing, equiaxed particle size, equiaxed packing fraction, heat transfer coefficient, and material …
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A rotating disk study of impurity segregation in aluminum alloy solidification
… impurities are exacerbated by convection-induced macrosegregation of impurities within ingots, which leads to local regions of accumulation or depletion of impurity-containing intermetallic compounds. A small-scale rotating disk experimental approach was used to study the segregation of iron, the …
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Jet processing of direct chill cast aluminum ingots
Macrosegregation of solute elements during casting operations has been a subject of observation, discussion, and research for several hundred years. The unique casting conditions found in the Direct-Chill aluminum casting process can lead to significant accumulation and depletion of solute elements …
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Centrifugal infiltration of particulate metal matrix composites : process development and fundamental studies/
… proposed to avoid layering in coarse powders. Macrosegregation and microsegregation were limited in all samples. The interparticle spacings of these composites were smaller than the dendrite arm spacing would have been at equivalent cooling rates; thus, dendrite formation and microsegregation …
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Composition effects on macroscopic solidification segregation of superalloys
… the composition effects on solidification macrosegregation, i.e. freckles, in superalloys. First, the freckling mechanism of superalloys is developed using the physical simulation of freckle formation in specially designed model alloys. It is found that freckles originate from dendrite …