| 摘要 |
1,225,404. Metal treatment Deoxidation. KAISER INDUSTRIES CORP. July 22, 1968 [Aug.3, 1967], No.34948/68. Heading C7D. Ferrous metal substantially free from oxygencontaining impurities is prepared by lowering the dissolved oxygen content in a preliminary deoxidation to not more than that given by the formula Log 10 %0 = 7640/T(‹ K)+2À84 and, if aluminium is used for this deoxidation, not more than that which is related to the aluminium present by the formula Log 10 [(%Al)<SP>2</SP>. (%O)<SP>4</SP>] = -79600/T (‹ K)+32À15, separating the preliminarily deoxidized metal from deoxidisation products and subjecting it to further treatment. The further treatment involves preparing a chamber lined with refractory containing 3À5% Feo or less which will not yield oxygen to molten metal containing aluminium as a deoxidizer, passing a non-oxygen-yielding gas into the chamber, adding a stoichiometric excess of aluminium over that theoretically required to deoxidized the metal, introducing the metal into the chamber, maintaining the chamber above the melting point of the metal until deoxidation has reduced dissolved oxygen in the metal to not more than 0À006% by weight and separating insoluble material from the deoxidized molten metal. Other agents such as hydrogen or carbon may be used for the preliminary deoxidation. |
