| 摘要 |
<p>1,236,123. Deoxidizing steel. INTERNATIONAL HARVESTER CO. June 19, 1969 [June 24, 1968], No.31076/69. Heading C7D. To reduce the formation of nozzle deposits in the tundish of a continuous casting plant the steel is deoxidized before pouring with a deoxidizer selected from:- (a) a rare earth metal (b) a compound of rare earth metal other than an oxide (c) yttrium metal (d) a compound of yttrium other than an oxide (e) a mixture of any of the agents (a) to (d) (f) scandium metal (g) scandium silicide (h) an actinide metal (i) an actinide silicide, the quantity used being such that at least ¢ lb. of metal is added per ton of steel. Preferred compounds are the silicides but others, particularly chlorides and carbides may be used. A particularly favoured metal is praesodymium, or misch metal may be used. In an exemplified process steel is tapped into a ladle, where silicon is added, followed by manganese together with any other alloying additions, and finally by the rare earth metal deoxidizer when about 65% of the steel is in the ladle.</p> |
