US1580647A

US1580647A - Process for treating ferrous metal to prevent corrosion

Info

Publication number: US1580647A
Application number: US447772A
Authority: US
Inventors: George D Breck
Original assignee: Individual
Current assignee: Individual
Priority date: 1921-02-25
Filing date: 1921-02-25
Publication date: 1926-04-13
Anticipated expiration: 1943-04-13

Description

' April 13 1926. 1,580,647

G. D. BRECK PROCESS FOR TREATING FERROUS METAL TO PREVENT CORROSION Filed Feb. 25, 1921 Patented Apr. 13, 1926 UNITED STATES GEORGE. D. BRECK, OF CLEVELAND, OHIO.

PROCESS I FOR TREATING FERROUS METAL TO PREVENT CORROSION.

Application filed February 25, 1921. Serial No; 447,772.

To all whom it may concern: I

Be it known that I, GEORGE D. BRECK, a citizen of the United States, residing" at Cleveland, in the county of Cuyahoga and 5 State of Ohio, have invented a certain new and useful Improvement in Processes for Treating Ferrous Metal to Prevent Corrosion, of which the following is a full, clear, and exact description, reference' beinghad to the accompanying drawings. This invention relates to the treatment of ferrous metal for the purpose of preventing corrosion. The fundamental object is the provision of a tube or pipe so treated, either-internally or externally or both, as to be usable for the economizers of steam boilers, or feed water heaters, since it is well known that ordinary steel pipes become corroded very rapidly when put to this use,

interiorly .because of the air, gas, or chemical substances dissolved in the water, and exteriorly because of the acid deposit con-. densed thereon from the furnace gases, or surrounding atmosphere. However my invention is not limited to this use inasmuch as a tube which has sufiicient resistance to corrosion for the purpose indicated is also usable in numberless other relations in the arts, and a process which will produce such a tube is equally applicable to the-production of ferrous metal articles for a great variety of different technical purposes,

whether subjected to hot, cold, wet, dry,

acid, alkaline, climatic or other injurious conditions; and I hereby declare my purpose to claim and secure my invention for all uses to which the same maybe applicable.

Subsidiary objects of the invention are the provision of a method of treating ferrous metal which is applicable to commercial, hot-rolled or forged, steel products and of all manner of cross section; which can be employed without departing from th established commercial methods ofsteel rolling; which is applicable to steel in the duetile state and is not restrictedto castings as in the case of many non-corrodible compositions heretofore suggested; which does not materially decrease the flexibility or duetility or other physical properties of the ma terial; which can be performed with commercial and inexpensive materials; the pros vision of certain new and improved articles and com ositions of matter; while other ob jects an advantages of. the invention will become apparent as the description proceeds. The essence of my invention resides in'the superficial application to a ferrous metal while rendered plastic by heat, of a protective metal or alloy in finely divided form, and immediately incorporating the a same' into the ferrous metal by'mechanical working such as rolling or forging, the temperature of the ferrous metal being below the melting point of the added material. I do not restrict myself to the use of any one metal or alloy excepting that the applied material inust be one which will alloy with the ferrous metal with the production of a solid solution alloy' forming a coating which is highly resistant to corrosion and is so closely adherent as not to scale or peel oif; and further that it should possess a 'sufliciently high melting point to withstand all ordinary vicissitudes of use. These considerations alone exclude the employmentof material consisting of or containing any large proportion of such ingredients as tin,

lead, zinc, arsenic,,antimony, bismuth, cadmium, or the like low melting-point metals. The material which I specially prefer is chromium or an alloy thereof, such as ferrochrome, or a mechanical'mixture of finely divided chrominum and iron; silicon also can be used to "advantage in many cases, especially in association with other materials such as iron, chromium or aluminum. All these materials are characterized by the production of an impervious, adherent, insoluble alloy. Thus a commercial ferrochrome containing a rather large percentage of silicon. affords the desired chemical advantages together with the physical property of being not unduly difficult to pulveriz e. Also the mixture of finely divided iron and chromium which is produced when chromite ore is reduced at temperatures' below the melting point of iron or chromium, forms a very convenient material.

-This -1naterial, mixed if desired with a suitable fiuxing compound, is sprinkled on the surface ofthe white-hot blank, slab or billet justprior to its passing through the rolling mill, whereupon the pressure causes a true alloying-of the ingredients even though the temperature be not sufliciently high to produce true fusion of the applied materials. In fact it' is better not to have fusion of these materials since withfusion they become mobile and tend to segregate into drops and are removed by the rolling or forging operations Whereas if fusion is avoided they remain in place. Before applying this treatment I preferably roll or forge the metal sufiiciently toward its finished dimensions so that the sulisequ'ent operations shall .not serve to destroy the applied coa'ting, reheating if necessary just prior to applying the powdered'or .granuiar material. Also the nature of the operation first performed after such application .is'

preferably one which does not greatly change the shape ofthe metal section but opposite side and immediately re-roll the faces; Fig. 7

only incorporates the added material intimately therewith, although this is generally 'altended with a decrease in the thickness of the blank accompanied by a corresponding spreading. After the coating is thus'fixed in place the article can be repeatedly rolled or forged, the surface layers expanding with the body parts throughout a considerable range of manipulation. Thus for example the blank may be circled into the form of a tube, having the coating either inside or outside,-or may be rolled into an I beam or other desired cross-section. In case it be desired to coat both sides 1 effect this byinverting the billet immediately after it has passed through the first rolls, apply a s1m1- lar coatmg of powdered ,materi'al upon its same, the smallest possible time being permitted to elapse between the two treatments so as to avoid unnecessary cooling.

In the drawings accompanying and forming part of this ap lication Fig. 1 1s a perspective viewshowing diagrammatically the performance of my inventiom'Figs. 2 3, and

4 illustrate the simultaneous extension of both coating and body upon working; Fig. 5 is a cross-sectional View of a tube having the described coating on its outer surface; Fig. (5 is a cross-sectional view of ablank having the described coating on both surillustrates a tube, having the described coating on both surfaces; and F 1g. 8 is a cross sectional view of an I beam treated as herein described.

-'same is 'cirel'ed and subse Describing the drawings by reference characters, 1 represents a white-hot,steel or iron, sheet or'billet, and 2 -2 the rolls between which the same is passed, same bein of any material known and used for tl at purpose, such as chilled cast 1ron, '3 represents the coating of applied pulverized materi'al prior to the rolling and 4 represents a mechanical device of any suitable type adapted to shower the materialupon theentire surface of the metal in a uniform layer of the desired thickness. 5 illustrats'the body and 6 the coating ofthe'resulting sheet or plate. \Vhen made into tube form the welded iin the usual Imanner-a ong the flougitudinal'line 77. In case of a-hot'rolle'd 'uently seam tube the coating can be applied during the rolling process and a seamless tube secured with the ncn corrodible surface I have decles are useful not only' in connection withboilcrs and their accessories, but also in bridges and structural works exposed to climatic rusting; to furnaces, stove parts, and metallurgical appliances exposed to high temperature corrosion; to various purposes scribed.- 8 indicates a preheating device such as .a as burner which may be used if desired. y improved compound metal artiwhere chemical corrosion is encountered;

and in numerous other situations.

It will be understood that I do not restrict myself to the operation of rolling as the sole means of incorporating the powdered ingredientswith the ferrous metal but have merely illustrated this as a type of,

mechanical working which involves pressure and which can also be relieved by such other steps as forgmg or hammering; also that I do notrestrict myself-t0 steel, since wrought iron, charcoal iron, and other Varieties of ferrous metal can be treated in this way, and also such special alloys as nickel, steel, vanadium steel, and the like; I do not restrict myself to any particular degree of fineness of the applied coating, nor to any shape of finished article, and generally that I do not restrict myself in anywise except as specify cially set forth in the annexed claims.

,Having thus described my invention what I claim is:

1. The process of producing non-corrodible meta steps of heating a slab or sheet of ferrous 'metal to a high temperature short of melt ing, covering the [same with a superficial coating of a finely divided metallic subelements which contains the containing finely divided metallic chromium i or an alloy thereof, incorporating such,

coating into such slab or blank by mechanical pressure, and subsequently reducing the slab. or blank to finished form by repeated rolling operations.

3. The vprocessof treating ferrous metal to prevent corrosion which contains the step of rolling pulverized 'ferro chrome 'into the surface thereof at whiteheat. I v

4. he process of rendering steel incorrodible which contains the-step of=rolli-ng into the-surface thereof at whiteheat a=- finely divided metallic substance which contains chromium-a 5. The process of producing an incorrodible article which contains the steps of rolling pulverized ferro chrome mechanically into the surface of a white hot billet of ferrousmetal and subsequently continuing the rolling until the desired shape is obtained and hot billet of ferrous metal, afterwards circling the resultant sheet into tubular form and welding the edges together longitudinall V 7 The process of making an incorrodiblc tube which contains the steps of heating a steel blank to a temperature of plasticity, covering the same with a finely divided metallic substance, -which when alloyed produces an impervious adherent, insoluble coating which is infusible at the temperature of such blank, incorporating such substance into said blank by mechanical pressure, expanding such blank into a sheet by pressure, and afterwards circling said sheet into a tube and welding the "edges of the sheet to gether.

8. As an article of manufacture a hot rolled ferrous metal section having a superficial coating of chromium alloy formed thereon in situ.

9. A noncorrodible tube made of hot rolled ferrous metal having its inner surface coated with an unbroken abherent superficial alloy containing iron and chromium.

"Intestimony whereof, I hereunto aflix my signature, GEORGE D. BRECK.