Vacuum Arc Remelting (VAR)
6Pagine

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table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:11.00pt "Impact", sans-serif; } .font1 { font:13.00pt "Impact", sans-serif; } Metallirgy of the Vacuum Arc Remelting Process The VAR ingot's solidification structure ot a given matriel h o fundion of the locof solidf鯯calion rate ont) the temprature gradient at the liquid/solid interface. Ta achieve a direcled dendrrtfc primary structure, a relolively high temprature gradient at the solidification front must be moinloined during the entire remelting process. The growlh direction of the cellular dendrites conforms...

table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:11.00pt "Impact", sans-serif; } .font1 { font:68.00pt "Impact", sans-serif; } ■ Ff eckles ond white spots hove o much greoler effect on materiol properties as compared to Iree ring potterns. Both defects con represent o signifkant cause for prmatur foilure of turbine disks in aircraft engines. Freckles are dark-etching circuler or nearly circulor spots tha驯 are generolly rich in cor bides or carbide forming lments. The formation of freckles is usuolly a resuit of a high metol pool rfepth and somefimes of a...

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