US1356342A - Manufacture of nickel-steel - Google Patents

Description

a citizen of the United States, residin warren STATES PATENT. oFFicE.

PERCY FOOTE COWING-,'0F NEW YORK, N. Y., ASSIGNOR 0F ONE-HALF TO HOWARD FIELD CALPPELL, OF NEW YORK N. Y.

. MANUFACTURE OF 'NICKEL-STEEL;

N 0 Drawing.

To all whom it may concern:

Be it known that I, PERCY Foo'rn Cowmc,

at New York, in the county of New ork, State of New York, have invented cer-' tain new and useful Improvements in Manufacture of Nickel-Steel; and I do hereby declare the following to be a full, clear, and exact description of. the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to the manufacture of nickel steel by introducing the nickel in the form of a product obtained as a cathode deposit in an electrolytic process of refining nickel copper matte. In the manufacture of nickel steel by combining steel and metallic nickel, it has been found very difficult to incorporate the nickel uniformly so as to secure a homogeneous alloy free from flaws or hollows.

I have found, that, by substituting for' nickel, in the customary process 'of producing nickel steel alloys in a crucible, open hearth or electric furnace, the nickel-iron material obtained as a cathode deposit in an electrolytic process of refining nickelcopper matte, the oxidation of the -nickel which is one of the difficulties in the ordinary production of nickel steel is reduced to a minimum.

In the practice of the invention, anickel iron material obtained-as a cathode deposit in the electrolytic separation of copper and nickel from copper-nickel compounds may be used. Such nickel-iron material may be obtained from a nickel-copper matte produced in accordance with the usual practice.

- The nickel-copper mattes, as obtained from the ore by smelting, contain considerable iron, and-it is therefore desirable to subject the smelter-matte to bessemerizing or similar treatment in order thereby to discard as muchiron as practicable so as to produce a matte high in nickel and copper and low in iron. Ithas been found that the iron seldom exceeds one per cent. Inthe preferred practice, the bessemerized matte is then subjected to an oxidizing roast to practically eliminate sulfur, and is' thereafter. reduced to a nickel-copper alloy whose relative proportions of nickel and copper will vary with the relative proportions of these metals in the ores from which the matte is de- Specification of Letters Patent.

Patented flct. 19, 1920.

Application filed June 16, 1920. Serial No. 389,478.

rived. Thus, forinstance, in' some cases the nickel-copper alloy will contain approximately 50% nickel and 50% copper, or it mayhave as low a percentage as 25% or thereabout, the nickel being then approximately 75%. These percentages are illustrative only and they may vary widely. Should it be found desirable to decreasethe percentage of copper in the nickel-copper alloy to be used as an anode, the bessemerized matte is subjected first to a partial roast, and is then leached withjdilute sulfuric acid in order to dissolve out and remove a part of the copper. The leached residue may then be reduced to form a nickel-copper alloy, still'containing a notable percentage of sulfur; or, should it be deanodes is then treated in such manner as to replace the copper by, iron, or by nickel and iron; as, for instance, by cementation (which I prefer). or by electrolysis. Nickel and iron in the solution thus obtained may then be electrolytically deposited upon a suitable cathode. Should cobalt be present the nickel-iron in the cathode deposit, and would accompany the nickel-iron into the finished steel.

As an instance of one way of practising the invention, I may recite the results 0btained starting with anodes containin approximately 68% of nickel and 27 %o copper. The dissolving electrolyte employed was a solution of ferrous chlorid and nickel chlorid of a specific gravity ofabout 1.15,

and was used at a temperature of about 70 C. The relative proportion of, ferrous chlorid to nickel chlorid in this electrolyte was such that the ratio of the iron to the nickel was as 16 to 84. Under these conditions, on the passage of the current, nickel and copper of the anodes went into solution The solution conin thissolution it would be associated with ing nickel and iron therefrom upon a suitable cathode, and was then reused as the dissolving electrolyte thus completing a cycle. In this instance, the current density,

at anode and cathode, was about amperes to the square foot, both for the dissolving electrolyte and for the depositing electrolyte. The nickel-iron product, suitable for addition to steel in appropriate proportion,

in accordance with the invention, contained approximately 84% of nickel and 16% of iron. I

The resulting cathode material, comprise ing nickel and iron. intimately associated, is then used in the place of nickel in the customary process of producing nickel steel in a crucible or furnace. The intimate relation of the molecules of nickel. and iron in the deposited cathode product is such that I have found that this product may serve to great advantage in the manufacture of nickel steel. The cathode product is of materially lower melting point than nickel, and, by reason of this lower melting point, dissolves readily in the molten steel inthe furnace, or it may be added as the steel is drawn, into the ladle, thus minimiz ing the oxidation of the nickel, which is one of the difficulties in the ordinary production of nickel steel in the open hearth furnace. So, also, the particles of the two metals, nickel and iron, being intimately associated, throughout the entire mass of the cathode product, it is easier to alloy the product with a bath of steel than if nickel only had been used; also in the manufacture of steel by the crucible process, it is correspondingly easier to obtain an intimate and ready fusion of the entire contents .of the crucible into a homogeneous nickel steel product.

One of the advantages, moreover, of the process is that the cathode material is entirely free from carbon, silicon, and oxygen, while phosphorous, sulfur and other like impurities, if present at all, are in very 'small amounts.

tained, and incorporating the resultant nickel-iron product with steel for producing nickel-steel; substantially as described.

2; The method' of producing nickel-steel, which comprises roasting bessemerized nickel-copper matte, leaching out a portion of the copper therefrom, producing nickelcopper alloy from the leached residue, dissolving sa-id alloy electrolytically to form a solution containing nickel and copper, substituting iron, or nickel and iron, for the copper in said solution, electrolytically depositing nickel iron from the nickel-iron solution thus obtained, and incorporating the resultant nickel-iron product with steel for producing nickel-steel; substantially as described.

3. The method of producing nickel-steel, which comprises electrolytically dissolving a nickel-copper alloy obtained from nickelcopper matte to form a solution containing nickel and" copper, substituting iron, or nickel and iron, for the copper in said solution, electrolytically depositing nickel-iron from the nickel-iron solution thus obtained, and incorporating the resultant nickel-iron product with steel for producing nickel steel; substantially as described.

PERCY FOOTE COWING.