Nonmetallic inclusions in magnetic alloys of the YuNDK35T5 type

Abstract

1. The results obtained only partially confirm the assumption that titanium nitrides and oxides impair the columnar solidification of YuNDKT alloys [4–6], since titanium oxides are not observed in the presence of aluminum, and titanium carbonitrides (nitrides) exist in the alloys without additions of sulfur and carbon, which along with the aluminum oxides may affect the solidification of the alloy. 2. The addition of sulfur and carbon results in the fact that some of the aluminum oxides and titanium carbonitrides are isolated from the heat by titanium sulfides and carbosulfides, which is full agreement with the assumptions made in [2, 11]. Other mechanism may also operate, as the result of which sulfur and carbon evidently form gaseous oxides that carry along solid particles of carbonitrides and aluminum oxides. This is confirmed by the formation of substantial clusters of corundum and carbonitrides in the head of castings with directional solidification when sulfur and carbon are added.