Abstract:
The effect of the melting conditions on the ductility of nickel-based superalloys is studied. The experimental results obtained are used to refine the formation mechanism and composition of nonmetallic film inclusions in as-cast nickel-chromium alloys. The magnesite lining of an electric furnace is found to serve as a secondary source for the transition of nonferrous and modifying impurities into a metal, which leads to the formation of a large number of nonmetallic inclusions. Film impurities located along the grain boundaries are shown to cause the low ductility of the metal during deformation. © 2007 Pleiades Publishing, Ltd.