Abstract
According to the research of the behaviour of nitrogel in the basic open hearth fhrnace and the basic electric are furnace, the following results were developed:
(1) The definite decrease in the nitrogen content of the molten steel during thelting in a basic open hearth furnace is visible after the occurrence of the increase in the oxygen content of the molten steel that has not Finished melting. A simple mechahical boiting would not decrease the nitrogen content of the molten steel.
(2) In a rimmed steel, the nitrogen causes an ingot segregation as in carbon, phosphorus, etc., but in somewhat less degree.
(3) In the basic electrie are furnace, the nitrogen content of the molten steel is already remarkable at the moment of melting-down. It is due to the existence of a period when the steel bath has not been fully covered by the slag. Therefore, the nitrogen absorption of the molten steel during melting may be suppressed by adding slag-formers such as lime and fluospar to the furnace bed before charging the steel scraps and thus covering the bath with slags from the primary stage of melting.
(4) In the electric arc furnace, the more free carbon (cokes) exists the greater is the amount of CaC2 found in the slag of the reducing period, while the nitrogen increases with the CaC2. No relation is found between the nitrogen in the slag and that of the molten steel.
