Browsing by Subject "thermal models"

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    Emissivity of Powder Beds
    (1995) Sih, Samuel Sumin; Barlow, Joel W.
    A simple model for estimating the emissivity ofthe surface of a powder bed from knowledge only ofthe bed porosity and solid emissivity is presented. Estimates by this model are compared with experimental measurements for powder beds of alumina, silicon carbide, and iron. Agreement within the uncertainty ofthe measurements, ± 10%, is obtained
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    Numerical Thermal Analysis in Electron Beam Additive Manufacturing with Preheating Effects
    (University of Texas at Austin, 2012-08-16) Shen, Ninggang; Chou, Kevin
    In an early study, a thermal model has been developed, using finite element simulations, to study the temperature field and response in the electron beam additive manufacturing (EBAM) process, with an ability to simulate single pass scanning only. In this study, an investigation was focused on the initial thermal conditions, redesigned to analyze a critical substrate thickness, above which the preheating temperature penetration will not be affected. Extended studies are also conducted on more complex process configurations, such as multi-layer raster scanning, which are close to actual operations, for more accurate representations of the transient thermal phenomenon.