US1537709A - Process of removing nonmetallic inclusions from iron or steel - Google Patents

Description

No Drawing.

' metallic Inclusions from Patented May '12, 1925.

f UNITED STATES PATENT OFFICE.

noon 0. Steam), or new YORK, n. Y.

I PROCESS OF REMOVING NONMETALIJLG INCLUSIONS FROM IRON OR STEEL,

To all whom it may concern:

Be it known that I, HUGH O. SICARD, a citizen of the United States of America, and a resident of the city ot'New York and State of New York, have invented a. certain new and useful Process of Removing Non- Iron or Steel, of

-which the following is a full, clear, and

exact description.

In general my process relates to a'method of removing any non-metallic inclusions from iron or steel, and in particular it relates to a method of removing the oxides of metals from iron or steel.

It is the common practice ot the art in making steel or ingot iron of any low carbon content to oxidize the carbon in a basic open-heartlrfurnace or in an electric furnace until the'percentage has reached the desired amount. This practice inevitably results in the formation of oxides of metals,

that is, non-metallic inclusions in the iron,

or steel. These oxides affect the properties of the iron and steel adversely, and as a consequence it has been the practice to use more or less aluminum as the deoxidizer, since the aluminum reacts with the oxides in the molten metal, In adding the aluminum as a deoxidizer the iron into a receiving ladle, and the aluminum is added thereto. -The aluminum immediately reacts with the various oxides suspended in the steel, thus forming alumina, which, as is .well known, is an extremely refractory oxide, and quite infusible at the temperature of molten steel. A result of this treatment is that the alumina derived from the alumi num, which has been used as a deox1d1z er, will be entrapped in the steel or iron during its solidification in the molds, and will thus aitect adversely" the physical properties of such iron or steel.

By means ot experiments. I have found that titanic oxide is asuitible fluxmg agent for alumina. Thus I have found that titanic oxide and alumina, when heated together form a much more fusible compound than is the alumina, and in the form either of artificially made oxide or as the natural titanic oxide, rutile, forms a cheaper and effective flux. l have found that in a wide range of roportions, the combination of titanic oxi e and alumina'iorms a low melting point compound, and, theretore, the addition of titanic oxide to molten steel or iron containing alumina forms a slag of the bath.

' the aluminum may or steel is tapped formation in a suitable 'tentsof the ladle titanic oxidc,

Application filed November 1, 1923. Serial No. 672,177.

latter which easily separates from the metal,

thus avoidingobjectionable inclusions 111 it.

My invention consists in the use of titanic oxide in any of its forms,natural or artiticial, as an addition to a bath of molten ron or steel with the object of fluxing' the alumina produced by the use of aluminum as a deoxidizer.

In carrying out my invention. I employ a furnace of any suitable type in which is formed a molten bath of metal. \Vhenthe furnace is tapped into the ladle, I throw in titanic oxide and it. melts rapidly. v \Vhen the ladle is about half or three-fourths full, the deoxidizing aluminum is added to the The aluminum is immediately oxidized, and the alumina thus produced fluxes with the titanic oxide, thus producingan iron or steel tree from any inclusions. Not only does the titanic oxide flux the alumina but it also combines with other oxides such as lime or the like. While the foregoing describes the usual method of carrying out my process, it should be noted that without departing therefrom beadded to the ladle first and later the titanic oxide may be added, or both the aluminum and the titanic oxide may be added simultaneously.

Having thus described my invention, what I claim is: a

1. A process of removing non-metallic inclusions from ironor steel comprising the furnace of a molten bath ofiron or steel, then tapping the furnace into a ladle, then adding to the conand then adding to the contents of the ladle aluminum. I 2. A ,process of removing non-metallic inclusions from iron or steel comprising the formation in a suitable furnace of a molten bath of iron or steel, then tapping the fursigned my name. I

' HUG-H G. SIGARD.

I have hereunto