US1019531A - Method of treating aluminum. - Google Patents

Description

UNITED STATES PATENT OFFICE.

AUGUSTE J'. ROSSI, OF NIAGARA FALLS, NEW YORK, ASSIGNOR TO THE TITANIUM ALLOY MANUFACTURING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE. 7

METHOD OF TREATING ALUMINUM.

1,019,531. Specification of Letters Iatent.

No Drawing.

To all whom it may concern:

Be it known that I, AUcIs'rn J. Rossi, a citizen of the United States, and a resident of Niagara Falls, in the county of Niagara and State of New York. have invented a certain new and useful Method of Treating -eign substances or gases, or both, dissolved or occluded therein, among which may be mentioned, as partlcularly deleterious, carbon and nitrogen, of which, notwithstandving its high reductive properties, aluminum appears unable to cleanse itself. The presence of such impurities impairs, according to their respectlve resulting effects m'the metal, desired physical properties such as strength, hardness, resistance to abrasion,

etc., and it becomestherefore desirable, in

many cases, that such impurities should if possible be eliminated as far as may be.

The ob ect of my present invention comprises such elimination from aluminum of present invention, in its broadest aspect, consists accordingly in the utilization of ,tltamum for the purpose and under the conditions specified.- The titaniumflmay be'so furnished .to the aluminum either by reduction of the oxid oftitanium in presence only of the molten aluminum, or by adding to latter only an alloy of titanium and aluminum, the results, as regards purification,

being the same in either case.

My said invention may be practiced as follows. In all instances I produce and maintain as preliminary abath of the mol- Patented Mar. 5, 1912.

Application filed March 10, 1911. Serial No. 613,624.

ten aluminum to be treated. Tothis bath I thenadd only a quantity of-oxid of'titanium proportioned to yield, on reduction thereof by the aluminum, sufiicient titanium to chemically combine with all impurities, including particularly the nitrogen present, thus forming nitrids of titanium. The temperature of the whole is then raised sufli ciently to insure the desired reaction be-- tween the aluminum and the oxygen of the titanium oxid, thus supplying the elemental titanium which in the absence of other constituents except. aluminum and its said impurities promptly combines chemically as.

aforesaid -with said impurities, including also the nltrogen present to form the re- .quired nitrids. These nitrids in turn combme chemically wlth carbon present. to

form cyanonitrids of titanium which, with the alumina formed at expense of the. oxygen of the titanium oxid, and compounds of titanium with constituents of said impurities, rise as a sort of slag to the surface of the bath thus freeing the latter proportionately of its carbon content as well as of other impurities. The aforesaid reactions having been accomplished, the resulting molten aluminum product is tapped out and allowed to coolv in accordance with usual metallurgical prac- -tice, and, sufficient titanium oxid having been added and temperature and' time afforded for the aforesaid reactions, should be found free of nitrogen and urified of undesired carbon, as well as a1 other impurities.

An alloy of aluminum and titanium may be employed iii-lieu of titanuim oxid in the practice of my said method, in which case, said alloy is added to the molten aluminum in quantity sufficient to impart enough titanium to combine as aforesaid with all undesired elements and compounds, 2'. e. impuri ties present, and particularly with nitrogen to thereby eliminate carbon also, and leave in the resulting product traces or not to ex-.'

ceed one one-half of one per cent. of titanium. The aluminum product treated as aforesaid is characterized by greater density, hard- 'ness and strength than the aluminum before its aforesaid treatment by myjnethod.

I be determined as will be understood by those skilled in the metallurgical art, and the proportions of titanium oxid or of alloy oftitanium thereto calculated in order to insure the aforesaid resulting product.

I am aware that molten aluminum has heretofore been utilized for the purpose of reducing titanium oXid and do not wish to be understood as claiming such use of aluminum as my present invention, which differs therefrom in that such priorutilizations of aluminum have involved entire destruction of all the aluminum present, this being in such cases used exclusively as a reducer, and the purpose being to secure a resulting product as far as possible completely freed from aluminum, Whereas the ultimate purpose and efl ectof my present invention comprise purification broadly and specifically elimination of nitrogen from the resulting aluminum product and removal therefrom of carbon as well as titanium.

I am also aware that it has been stated that an alloy of titanium and aluminum containing from one-half of one to ten per centum of titanium can be produced in a bath containing not only aluminum and oxid of titanium but also fluorids of metals more electro-positive than aluminum, etc., but neither is this my present invention which, by dispensing with the presence of such fluorids and other agents, enables the titanium present to act alone as hereinbefore described as a complete purifier of the aluminum, and this during a single heat,

whereby attained my novel product, as is impossible by saidprior procedures.

Vhat I claim as new and desire to secure combine chemically with said nitrogen and carbon, the said titanium being proportioned to secure a resulting aluminum product. containing less than one-half of one per centum of titanium.

2. The method of treating aluminum con-. -taining impurities lncluding nitrogen and 7 carbon, which consists in bringing said aluminum into molten state, adding thereto titanium oxid proportioned to satisfy chemical aflinities of all said impurities for titanium, raising the temperature of the resulting bath to one at which aluminum reduces said oxid, and then maintaining said temperature until resulting metallic titanium has combined chemically with said impurities including said nitrogen and carbon to secure a resulting aluminum product containing less than onehalf of one per centum of titanium.

AUGUSTE J. ROSSI.

W'itnesses \VALTER D. EDMONDS, PHIL P C. PECK.