US1845145A - Process of making an alloy - Google Patents

Description

-making cutting tools,

pos'sesse's3a high: and'permanent lustr"e suchasisrequired'or desirable in metals Patented Feb. is, 1932 JAMES B GRENAGLE, OF BALTIMORE, MARYLAND, ASSIG'NOE .OF ONE-HALE TO ane FE I

WILLIAM W. VARNEY, OF BALTIMORE, MARYLAND rnoonss or a AN LLOY.

No Drawing. Application died The object of my invention is the produc- 'tion of an alloying element which may be used either by itself in commercial production, or alloyed with other metals. 5 A further object of my invention is the production of an alloy that will withstand the corrosive effect ofthe surroundings in which it may be used and at the same time maintain the cutting edge of implements containing the same.

A further object of my invention is the producing of high speed steels now commonly used in which addition to having the required hardness necessary to .perform the functions in cutting operatlons, is extremely tough and has a very high melt- -ing point.

A further object of my invention is the pro- "duct-ion of an alloy of the character and characteristics set forth herein which is capable of being forged, hammered, or otherwise worked into various forms, ticular'ly adapted for'use. in the manufacture of knife blades, and surgical and dental instruments. y A further object of my invention is the providing of an alloy having the characteristics usually employed in the cutting of hard steels and manganese steels] M A'ffurther object of my invention is the production "of an alloy, as hereinsuggestcd,

foiknife blades, surgibfiiflnd'identfl imPle' mcnts. I

- -A further object of my invention is the productionof'an alloy as suggested herein, which is substantially free from injurious impurities, especially such impurities as carbon, silicon, sulphur and like materials which 45 seriously interfere with the non-tarnishing.

- properties of alloys.

Vilith the foregoing and other objects in view,fmy;- invention consists of the methods ,employed combination and arrangement of systems and means v as hereinafter specifically an alloy which is superiorto and which is parherein enumerated, and which is not attacked" by cutting compounds, caustics and, acids 0ctober21, 192a. Serial No. 401,374.

conium and manganese may be varied within 7 a considerable range. I have found that an alloy containing about 70% of uranium, 25%

zirconium and 5%-of magancse 1s artlcularly adapted for use in making high s eed tools, knife blades, dental and surgica instruments, and the like. I

I will describe one method of producing the alloy mentioned herein- I reduce ores containing oxides of uranium, zirconium'and natural oxide of manganese in an electric furnace in areducin atmosphere such. as is present when a cargmn crucible, orcarbon electrodes, are em loyed. I have discoveredthatthe mixture of oxides of uranium and zirconium melt at lower temperatures than either of the pure metals, so

that. the process of melting the oxides is more economical and can be more easily accomplished than melting the pure metals them- ;sclves. v

. The oxids are introduced into an electric furnace, rammed in and closely packed and covered with pure carbon, such as. lam

black, charcoal,'etc., and subjected to a big temperature, preferably, from about 2500 02600, degreesG. until a freely fluid alloy of iiranium "and zirconium is. obtained.

temperature is then slightly lowered to about 2300 to 2400 degrees (3., when the manganese in the state of a natural oxide is added;

' The alloy, after it has become is maintained at a temperature sufliciently high to keep it freely fluid for a substantia period of time, preferablyabout 15 minutes.

The temperature is'then reduced until the alby is in a less fluid condition, and this temperature is maintained for a considerable period, preferably for about l5 minutes to eliminate the sonims. Caution: If the alloy is kept in a freely fluid condition at a hig temperature for too long a time, it will have The ticles made are ground quired.

10%, i 'ing product is so soft that after being poured suiiiciently hard acrystalline structure when cool, and the duced temperature for a substantial period a high degree of the alloy after it of time, it is poured directly into suitable molds with proper neutral lining, and the arinto the required use.

The above alloy, having a proper lining of a neutral, highly refractory substance, product which is free from checks and blowholes, provided the flask and lining are heated prior to pouring. I heat the mold to1200-degreesF. The alloy above described'may, con tain some iron, up the least detriment to, the products produced. The alloy, after being cast in the mold, requires no further heat treatment or tempering before grinding into the shapes reuired. q I have found that this alloy may be advantageously added to or alloyed with iron,.a nd that the resulting alloy has certain superior qualities over high speed steels. The proportion of iron which may be alloyed with my alloy may range 'from'2% amount of iron which is added is increased. the alloy becomes softer. If an amount of iron between 2% and 10% be added to my ly surrounds the zirconium binding the metalloy, the resulting product need only be cast into molds and ground "into the shape re- If, however, the amount of iron which is added to my alloy is greater than d between 10% and 95%, the resultinto a mold it must be heat treated, or tempcred, in amanner similar to the heat treatment of high; speed 'steels before itwill be cutting tool. p. g

I have found that my alloy, when contain-' ing 10% or more of iron, may be readily forged between the critical range of temperatures of 1400 and 1800 degrees F.

One method of obtaining uranium oxide which I have used with satisfactory results, is as follows:

Theore is roasted with an alkali until thoroughly fused then washed with hot water until free of iron, and dissolved with HNO Evaporate the HNO solution obtained to a volume of about 40% and cool. After mak ing neutral with NH OH, add about 5% of P 11 0 and 15% of HPO; and heat the niXture to boiling, when awhite precipitate )t' uranium is formed. Cool to coagulate the precipitate, and wash and ignite to U 0 will be" somewhat therefore, of re-- been maintained at a rewhen poured into moldswill give a superior to possibly '2%, without" to 95%; as the not be lignited to be used as a high speed When uranium and zirconium are melted together theytend to separate into two layers v due to their different specific gravities and to the low solubility of either metal with reference to the otherwhen mixed together. Even" in the'liquid' condition uranium and zirconium do not mix completely, but form twolayers, one rich in uranium and the other rich in zirconium. When allowed to rest quietly at very high temperatures these two layers approach each .other in composition; in other words, the solubility of'each metal in the other increases with on the other hand, "thessolubility decreases with decreased temperature. V H

When uranium and zirconium are melted and stirred in fiIl6 dissemination of the two metals is brought about and maintained in the cooled alloy;- The metals. do not actually dissolve in each other, but the dispersion is so fine that the unaided eye is unable to distinguish the Separate metals, The microscope reveals theuranium constituent as a continuous phase completely surrounding the iine globules or separated particles ofzirconium. Examinaf tion with a micrometer microscope of the zirconium particles will show very fine minute crystal structure. The action of manganese causes the uranium to solidify first as a dentritic skeleton rejecting practically all of the zirconium, the dentritic skeleton finally becoming continuous and completely surrounding the disconnected particles of zirconium. After the uranium is frozen and the allov'continues to cool, the dentriti c skeleton completeals together in what appears to be a solidal- 103 by means of a continuous net work.

The separated crystals of zirconium C3115 away from the alloy, for they are enclosed in the continuous skeleton of uranium which requires a hightemperature to melt.

One method of obtaining zirconium oxide, which I have used with satisfactory results, is as follows:

Brazilian ore is thoroughly crushed, ground and pulverized (150-200 mesh) and added to a molten bath of equal parts of sodium chloride, sodium carbonate and sodium bisulphate. A temperature high enoughto volatilize the alkalis must be reached, which may be determined by the amount of carbon dioxide liberated, and maintained at a dark red heat until all of the carbon dioxide is expelled. The major portion of the iron, practically all of the silica, and all of the accompanying rare earths having high solution pressure either go into solution and are recovered from the mother liquor, or, as in the case of silica, are completely vaporized and are driven oil with the carbon dioxide.

The resultant fused mass, thoroughly leached with water, leaving a the presence of manganese a after cooling is increased temperature;

eearee crystalline sodium zirconate which is decomposed by hydrochloric acid. All of the books I, and other writings which the applicant has examined, state that sodium zirconate is soluble in water; this the applicant finds to be a grave error, as he has found that sodium zirconate is insoluble in water, as a matter oi fact, the insolubility of the residue in water I is sufiicient proof thatonly zirconia is pres- 1 ent.

Further purification:

f The zirconate is then dissolved in hydro- V chloric acid (dilute) and evaporated to dryness, this being repeated to separate any silicaand to drive 0% such hydrochloric acid as 3 remained. The dried mass is leached with dilute HCl and zirconia precipitated as hydroxide with ammonia. Ihis hydroxide is dissolved in hot concentrated HCl, to a solu tion evaporated to dryness and the crude zirconyl chloride'washed with water, thus removing most of the iron present, The zirconyl chloride is then repeatedly crystallized from boiling HCl. This chloride still retains some silica which may be removed by dissolving in water and filtering; severai crystallizations from water giving a very pure chloride; For the complete removal of all impurities it is necessary to transform this oxychloride into tetrachloride and sublime it repeatedly. I On the ignition the chloride yields the oxide containing traces of chlorine, For the pure oxide it is necessary to precipitate the hydroxide, wash and ignite.

I use natural manganese oxide, in the mix ture above described.

I have discovered that not more than 95% of iron can be added to my alloy, as any greater percentage ofiron will form impuri 49 ties of iron'oxide which, upon slagging. 0E will cause the zirconium metal to burn to its oxidewitha resultant ferrio-zirconic oxid, resulting in a complete loss'of' alloy.

In thesespecifications and claims, when I use the term, alloy, 1- mean an a llotropio. mixture wherein the metalsundergo a physi cal change and'not necessarily a chemical change.

Having thus described my invention, what I claim and desire to secure by Letters Patcut is:

The process of producing a dentritic alloy containing uranium, zirconium and manganese consisting ofLco-mingling oxides of zirconium' and uranium, smelting the same in contact with carbon whereby a fluid melt of said two elements intimately associated is produced, then lowering the temperature of the said molten mass, and then adding the 6 manganese oxide for the purpose of difiusing the uranium to form the dentritic structure.

JAMES B. GRENAGLE.