US1714177A - Ferrous alloy - Google Patents

Description

Patented May Z1, 1929.

UNITED STATES 1,714,177 PATENT OFFICE.

LEWIS W. MALLASEE, OFIITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WILLIAM I MALLASEE, OF PITTSBURGH, PENNSYLVANIA.

FERRoUs ALLOY.

No' Drawing.

This invention relates to a ferrous alloy, and to the method of making the same.

An object of the inventionis to provide a steel of increased toughness,'that is of increased tensile strength, without detracting from the inherent hardness of the steel and with an increase in the ability of the steel to take a high temper.

Another object of the invention is toprovide an alloy which is dense and homogeneous in its structure, and which is stamless and resistant to corrosion.

Another objectof the invention is to provide an alloy, having these qualities, in which the alloying materials are relatively inexpensive, thus permitting their use in steel of various grades to be used for various purposes.

lVhen the steel is made by the crucible process, the'alloy is introduced into the pot at the end of the melt, and approximately ten minutes before pouring. \Vhen it is made by the open hearth process, it is preferably introduced after the blast has been discontinued and before the metal is poured from the converter, or may be placedin the ladle. The reason for this general time element is to secure a thorough dissemination of the alloy through the molten metal, while avoiding the introduction of the alloy so early in the process of making the steel as to give an unnecessary opportunity for the volatilization and consequent loss of the alloying material.

The alloy used is tin, which is associated with a suitable material, such as aluminum, capable of fluxing in the molten ferrous metal and preventingthe volatilization of the tin therefrom. The tin is introduced in a quajntity no less than one and one-half ounces of tin for each hundred pounds of the ferrous metal. It has been found that tin in a materially less quantity fails to contribute the desired qualities to the steel in such degree as to render its use of materialadvanta e. The greatest efiiciency is obtained by ad ing-the tln in the quantity of two and one-halfounces of tin in each hundred pounds of the ferrous metal. Itfhas been found that when tin in excess of two and one-half ounces for each hundred pounds of ferrous metal is added, the additional advantageous effect is not in proportion to the increased quantity of the alloy. It should be understood that for certain purposes tin Application filed September 22 1927. Serial No. 221,402.

in cxcessof two and one-half ounces per hundred pounds of ferrous metal may be added. The effect of the tin is obtained 11'- respect ire of the carbon content of the steel.

\Vith low carbon steel, such as sixty carbon steel, however, the effect is more marked, be cause a proportiomilly greater improvement in the quality of the steel is obtained. This is of great importance in, that it permits an improvement in the quality of steel for railway rails, structural use, and the like, by the employment of an alloying material of relatively low cost.

\Vith the tin aluminum is added in a quans tity-at least equal to that of the tin. Both substances should be in the elemental, or me tallic state, and desirably in divided form such as the form of shot.

The quantity of aluminum, as given, is in excess of that employed when the function of the aluminum is merely to remove gases from the melt and prevent their occlusion in the ferrous metal. The aluminum oxidizes to form a thick coating over the molten metal in the receptacle, thereby apparently preventing the escape of volatilized tin and enforcing its thorough dissemination through the body of ferrous metal. It is not at present known if any portion of the aluminum remains in the metallic mass, and.

whether-or no it has any more specific elfect in causing the inclusion of the tin therein.

The resulting ferrous alloy possesses highly advantageous qualities. It possesses an increased tensile strength, without a diminution of its inherent hardness and with increased capacity to receive a high temper.

It has an unusual resistance to corrosion, and has a surface which does not stain upon contact with mild acids and other substances which usually produce such effect. Apparently a body of the metallic alloy is un than ,one and one-half ounces of each for each hundred pounds of the ferrous metal. '3. The method of making-a ferrous alloy whichconsists in adding tin and aluminum 5' to the ferrous metalwhile itis in a molten condition and at a p'ouring temperature, the

ingredients being added in a approximately kwo and one-hal each for e'achhundred pounds of the ferrous metal;

uantity oi ounces. of

.hand.

' 4. Tl1e method of making a ferrous zilloy which consists-in adding tin and aluminum to'the'ferrous metal while it is in a molten condition and at a pouring temperature, 'the LEWIS w. MALLASEE.