US1700460A - Metallurgical process - Google Patents

Description

Patented Jan. 29, 1929.

. STATES PATENT-OFFICE.

JOHN H. WHITE, 01? CRANFORD, NEW JERSEY, ASSIGNOR T0 BEJL TELEPHONE LABO- RATORIES, INCORPORATED, OF NEW YORK, .N'. Y., A CORPORATION OF NEW YORK.

' METALLURGICAL PROCESS.

No Drawing.

. small amount of manganese followed by-a small amount of magnesium. The added metals act as cleansing agents, the manganese combining with the sulphur and the magnesium combining with the gases, such as oxygen, etc.

It has been found, however, that ingots produced in this manner are not uniformly forgeable due, it is thought, to small amounts of brittle nickel sulphide which remain, the theory being that nickel sulphide having a much lower melting point than nickel, the

nickel sulphide forms between the grains of Y nickel upon solidification, thereby making the casting brittle and very difiicult to work. A sulphur content as small as .005% is enough to make the metal brittle.

Among other addition agents which have been proposed, zirconium may be mentioned. This has been used to increase workability of steel and certain alloys, but is .found to be unsatisfactory for use with nickel and nickel alloys.

According to the present invention, nickel and alloys of nickel are made uniformly forgeable by adding to the molten metal a small amount of vanadium, followed by the addition of a small amount of magnesium. In preparing the ingots, nickel, for example, is melted in a suitable furnace. Near the end of the melt an alloy of vanadium and nickel, containing about 25% vanadium, is added in an amount sufficient to make the vanadium content of the molten bat-h about 0.25% to 0.50%. This is followed shortly before the end of the melt by addition of about 0.10% magnesium. Due-to the violence of the action when pure magnesium is added, an alloy of nickel and magnesium may be employed.

Vanadium has a greater affinity for sulphur than has nickel, and the nickel sulphide is broken up and the vanadium combines with the sulphur to form vanadium sulphide. The vanadium sulphide solidifies at a much high- Application filed December 15, 1926. Serial No. 155,113.

er temperature than nickelsulphide. Dur-.

ing the solidification the vanadium sulphide is believed tobe entrapped within the grains of nickel and therefore does not form in the grain boundaries. If the metal is maintained in its molten state long enough, and if sufficient sulphur is present, at least a portion of the vanadium sulphide will rise to the surface and may be drawn ofi as slag.

The vanadium remaining in the molten nickel after the formation of vanadium sulphide combines with a portion of the oxygen, forming an oxide of vanadium. The sub-- sequent addition of the magnesium to the bath completes the deoxidizing ,process. Most of the oxides of vanadium and magnesium slag off at the. top of the bath. The casting produced by this process is tough, free from blow holes and capable of being" worked without difficulty.

nickel and iron which are described in U. S.

Patent No. 1, 586,884 to G. W. Elmen, issued June 1, 1926. In the manufacture of such alloys it is desirable to keep the carbon content of the alloy as low as possible and hence electrolytic nickel, having a carbon content of 03% or less, is employed. This nickel is plated from a sulphate solution and since it is somewhat porous a small portion of the electrolyte is entrapped in the pores When the plated metal is melted the electrolyte 1s decomposed and sulphur is absorbed by the molten nickel. By employing vanadium and magnesium as cleansing agents, the sulphur is combined with the vanadium and the alloy is made uniformly forgeable without deleteriously afiecting its magnetic properties.

What is claimed is:

1. The process of comprises adding small amounts of vanadium and magnesium to the nickel while in its molten state, to render the nickel forgeable.

2. The process of treating nickel, which comprises adding a small amount of vanadium followed by a small amount of magnesiumto the nickel while in its molten state, to render the nickel forgeable.

3. The process of treating nickel, which comprises adding less than 1% of vanadium and less than 1% of magnesium to the nickel while in its molten state, to render the nickel forgeable.

4c. The process of treating nickel, which treating nickel, which comprises adding about 0.25% to 0.50% of small amount of magnesium to the alloy vanadium and about 0.10% of magnesium to while in its molten state, to render said alloy the nickel While in its molten state, to render forgeable. 10 the nickel forgeable. In witness whereof; I hereunto subscribe 5 5. The process of treating an alloy of my name this 14th day of December A. D.

nickel and iron, which comprises adding a 1926. small amount of vanadium followed by a JOHN H. WHITE.