US2492019A - Steel wool steel - Google Patents

Description

Patented Dec. 20, 1949 STEEL WOOL STEEL James R. Thompson, Shaker Heights, Ohio, assignor to The American Steel and Wire Company of New Jersey, a corporation of New Jersey No Drawing. Application January 30, 1947, Serial No. 725,283

5 Claims. (Cl. 75-123) This invention relates to improvements in steel wool steels and the steel wool made therefrom, and more specifically to an improved steel wool and steel wool steel made by the basic openhearth process.

Heretofore, steel wool has been commonly made from Bessemer steels despite the fact that only the lower 60% of Bessemer ingots could be used for making wool wire due to excessive segregation in the upper 40% of such ingots. I have discovered that by adding controlled amounts of nitrogen and bismuth to basic open-hearth steel of the analysis hereinafter set forth, that it can be used for making wool wire. Such steel is considerably more economical for such purpose in that 80% of the ingots are usable for making this product.

It is accordingly an object of the present in vention to provide an open-hearth steel suitable for making steel wool.

It is a further object to provide a steel wool steel and steel wool made therefrom having improved characteristics.

In accordance with the teachings of my invention, the steel wool steel should have the following analysis:

Carbon 25% max. Manganese .65 to .95% Sulphur 05% max. Phosphorus .110% max. Bismuth .01 to 04% Nitrogen .004 to 015% Balance substantially iron except for residual amounts of other elements ordinarily present.

A specific example of suitable steel within the foregoing ranges is:

Per cent Carbon .13 Manganese .91 Phosphorus .086 Sulphur .043. Nitrogen .007 Bismuth .016

bismuth in finely divided form (20 -30 mesh) I since this gives the maximum recovery. The desired nitrogen content is preferably obtained by adding nitrogen bearing material such as ammonium sulphate, urea, cyanamide, or any other compound of nitrogen to the molten steel in quantities sufficient to impart the desired amount of nitrogen thereto.

By controlling the nitrogen and bismuth additions within the foregoing limits to basic openhearth steel of such composition, I have determined that a steel having improved qualities for making steel wool is obtained. The steel shavings obtained therefrom are very long and fiber like and being soft do not break very readily. When used for the common abrasive work, for which the steel wool pads are intended, the strands do not break up into sharp needle-like fragments but instead break up into soft crumblike particles. The strands are much longer than those obtained from shaving conventional Bessemer wool wire and, in addition, the fractures of the Bessemer steel are more jagged and thus tend to cut the hands of the user or actually become embedded in the user's skin. The fractures of the fibers of basic open-hearth steel containing nitrogen and bismuth in accordance with the teachings of the invention are more blunt and thus do not have the tendency to penetrate the users skin. Moreover, because of the less tendency of the fibers to fracture, the useful life of the pads of wool made therefrom is materially increased.

While the steel of my invention has been specifically described, various steels may be made within the composition ranges and scope of the following claims.

I claim:

1. A steel containing 25% maximum carbon, .65 to .95% manganese, 05% maximum sulphur, .110% maximum phosphorus, .004 to 015% nitrogen, .01 to 04% bismuth, the balance iron and incidental impurities.

2. A basic open-hearth wool steel containing 25% maximum carbon, .65 to .95% manganese, 05% maximum sulphur, .110% maximum phosphorus, .004 to.015% nitrogen, .01 to 04% bismuth, the balance iron and incidental impurities.

3. Steel wool composed of basic open-hearth steel containing 25% maximum carbon, .65 to .95% manganese, 05% maximum sulphur, .110% maximum phosphorus, .004 to 0.15% nitrogen, .01 to 04% bismuth the balance iron and incidental impurities.

4. A steel wool steel containing .25% maximum carbon, .65 to .95% manganese, 05% maximum sulphur, 004 to 015% nitrogen, .01 to 04% bis- 3 muth and the balance iron and incidental im- UNITED STATES PATENTS purities.

5. A basic open hearth steel wool steel contain- 2 3 2 5 Z a1 ig ing 25% maximum carbon, .65 to .95% mangan- 2378548 1945 ese, .()5% maximum sulphur, .01 to .04% bismuth 5 gg u e and the balance iigon and incidental impurities. FOREIGN PATENTS Number, Country; Date JAMES THOMPSON- so9,a15 France Mar. 10, 1937 REFERENCES CITED OTHER REFERENCES The following references are of record" in the Basic Open Steel Making, page 336. Published file of this patent: V in;1941i by The Institute of Mining and Metallurgiqal, Engineers New York.