Which of these factors causes more porosity to form toward the interior of a casting rather than toward the outside? (a) Gasses are less soluble in the solid metal than the liquid, so solidified areas push dissolved gasses toward the interior. (b) Casting under a vacuum causes gasses near the liquid metal surface to be drawn out of the liquid during solidification. (c) The feeding structures of the mold are designed to force entrapped air into the center of the casting. (d) Draft on the mold wall forces air bubbles toward the interior of the solidifying metal. (e) None of the above Non-eutectic alloys (most commercial alloys) solidify over a temperature range. Which of the following statements explains how this affects the casting process. (a) Solidified non-eutectic alloys are especially difficult to remove from metal dies (b) Non-eutectic alloys have significantly less fluidity than pure metals or eutectic alloys. (c) Non-eutectic alloys solidify starting from the outside of the casting. (d) Cooling passages must be put into molds for these alloys to reduce the temperature range over which solidification takes place. (e) None of the above

Which of these factors causes more porosity to form toward the interior of a casting rather than toward the outside? (a) Gasses are less soluble in the solid metal than the liquid, so solidified areas push dissolved gasses toward the interior. (b) Casting under a vacuum causes gasses near the liquid metal surface to be drawn out of the liquid during solidification. (c) The feeding structures of the mold are designed to force entrapped air into the center of the casting. (d) Draft on the mold wall forces air bubbles toward the interior of the solidifying metal. (e) None of the above Non-eutectic alloys (most commercial alloys) solidify over a temperature range. Which of the following statements explains how this affects the casting process. (a) Solidified non-eutectic alloys are especially difficult to remove from metal dies (b) Non-eutectic alloys have significantly less fluidity than pure metals or eutectic alloys. (c) Non-eutectic alloys solidify starting from the outside of the casting. (d) Cooling passages must be put into molds for these alloys to reduce the temperature range over which solidification takes place. (e) None of the above

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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