US1501356A - Method of treating molten-metal coating baths and bath produced thereby - Google Patents

Description

Patented July 15, 1924.

EDWIN R. MILLRING, OF BELLEVILLE, NEW JERSEY, ASSIGNOR TO AMERICAN MACHINE & FOUNDRY COMPANY, A CORPORATION OF NEW JERSEY.

ivrn'rnon'or TREATING- MOLTEN-METAL COATING BATES AND BATH rnonocnn THEREBY.

No Drawing.

To all whom it may concern:

Be it known that I, .EDwIN R. MILLRING, a citizen of the United States, residing at Belleville, in the county of Essex and State v of New Jersey, have invented certain new of molten lead designed for use in coating iron or steel or other metals, with a protective covering to prevent corrosion or oxidation. The presence of phosphorus in a molten metal coating bath is very advantageous and desirable, in that it gives the metal to be coated an afiinity for the metal of the bath, and it assists in other ways very materially in bringing about the close union and adherence of the coating metal to the metal to be coated. It has been proposed to incorporate phosphorus in molten lead baths, by the use of phosphor-tin as the incorporating medium, and in such cases there is introduced into the bath with the phosphorus, a considera ,le amount of tin. For certain purposes suc tin in the bath is not undesirable, while in other cases it is preferable that no tin be present and that the metal of the coating bath be wholly of lead. According to my invention I incorporate phosphorus in the molten metal bath in a very eifective manner and without the addition of tin, by employing as the incorporating' medium an. alloy of phosphorus and lead; and the invention consists in the improved method of treating molten baths to incorporate phosphorus therein, and also the improved coating bath resulting from said treatment. a

The phosphorus lead alloy I employ consists structurally of lead having incorporated therein and distributed throughout the same, metallic phosphorus, also known as black phosphorus. This alloy may be made among other ways, by confining phosphorus and lead in the proper proportions say from 1 to 5% of phosphorus, in a sealed the incorporation of phosphorus in a bath Application filed. February 8, 1923. Serial 151'0. 617,843.

metal receptacle or bomb into which is introduced an inert gas such as nitrogen or carbon dioxide or the like, to displace the air. The bomb is then heated to a temperature'of about 650 C. for about six hours, which may be conveniently efiected by introducing the bomb into an electric furnace. The heat will cause the lead to become molten and the phosphorus to dissolve therein and be distributed throughout the molten bath, such action being aided by the pressure created. within the bomb, in the neighborhood of perhaps ten atmospheres. The phosphorus lead alloy thus formed may, while still in molten condition, be added to the metal bath in which the phosphorus is to be incorporated; or the contents of the bomb 7 may be allowed to cool and the molten mass to hardenin the form of an ingot, and in this form be added to the molten bathf In the treatment of molten metal baths, for instance lead baths, in accordance with my invention to incorporate phosphorus therein, the phosphorus lead alloy if in the form of an .ingot, is immersed in the bath and kept fully immersed therein, with the result that the. lead of the alloy will be reduced to molten condition and will mingle with the, lead of the bath, and the phosphorus will be liberated and will be absorbed in the bath without loss bybeing burned away. Orif the alloy is added in molten condition, the bomb in which it is made may be kept heated and the .molten alloy drawn off from time to time for addition to the bath as needed.

By the incorporation of phosphorus in metal baths through'the medium of a phosphor-lea'd alloy, I am enabled to introduce the phosphorus without at the same time incorporating any other ingredients. This capability is of advantage in the treatment of lead baths designed for instance for applying a protective coating to metals to prevent corrosion and oxidation, for which uses it is in certain cases desirable that the metal of the coating bath be wholly of lead. Such baths have had the phosphorus incorporated by using phosphor-tin as the incorporating medium, but with the result that a considerable quantity of tin is left in the .bath. By

the employment of phosphor-lead as the in- Q corporating medium in accordance with my invention, the phosphorus may be incorporated in the bath without introducing tin or any other ingredient.

While I have described my invention as applicable specifically to the treatment of lead baths, it will be understood that it is also applicableto the treatment of molten baths of other metals, the lead of the phosphorus lead alloy in any case mingling with the metal of the bath, and the liberated phosphorus vdissolving in the metal of the bath;

Having thus described my invention, what I claim is:

1. The method of treating molten metal baths to incorporate phosphorus therein, which consists in adding to the bath, an alloy of phosphorus and lead.

2.,The method of treating molten lead baths to incorporate phosphorus therein, which consists in adding to the .bath, an alloy of phosphorus and lead.

3. The method of treating molten baths to incorporate phosphorus therein, which consists in adding to the bath, lead containing phosphorus distributed throughout the same in the form of metallic phosphorus.

4. The method of treating molten lead baths to incorporate phosphorus therein, which consists in adding'to the bath, lead containing phosphorus distributed throughout the same in the form of metallic phosphorus.

5. The method of treating molten metal baths to incorporate phosphorus therein, which consists in adding to the bath, an alloy of phosphorus and lead in molten condition.

6. A coating bath for metals, consisting of molten metal having an alloy of phosphorus and lead fused therein.

7. A coating bath for metals, consisting of molten lead having an alloy of phosphorus and lead fused therein.

In testimony whereof I have affixed my signature hereto.

EDWIN R. MILLRING.