US331104A - Process of covering metallic objects with an electroplating of magnetic oxide of iron - Google Patents

Description

Unit dramas PATIENT rricn,

WVILLIAM H. \VINSLOIV, OF BROOKLYN, NEW YORK.

PROCESS OF COVERING METALLIC OBJECTS WITH AN ELECIROPLAIING 0F MAGNETIC OXlDlE OF IRON.

$PECIFICATION forming part of Letters Patent No. 331,104, dated November 24, 1885.

Application filed June 2, 1884. Serial No. 133,617.

To aZZ whom it may concern.-

Be it known that 1, WILLIAM H. WINs- LOW, a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented a certain new and useful Improvement in the Art of Covering Metallic Objects with an Electroplated Coat of Magnetic Oxide of Iron; 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.

My invention consists of the art of covering metallic objects with an electroplatedcoat of magnetic oxide of iron by first electroplating the metallic object with iron in the ordinary way, and then converting the electro-deposit of iron into magnetic oxide of iron, one way of accomplishing which is to subject the iron-plated object to an atmosphere of superheated steam.

In order that my invention may be clearly understood, I will proceed to describe it as applied to a copper electrotype. For iron plating such an electrotype, I have used with very satisfactory results a bath prepared from a solution of twenty (20) parts of salammoniacin one hundred (100) parts of wa ter electrolized by the use of two wroughtiron plates for anode and cathode, respectively. The point of proper saturation of the bath having been reached, which may be ascertained by the ordinary test method, the

- iron cathodeis removed, and the copper electrotype put in its place. The electrotype becomes rapidly covered with a deposit of iron. The plating must be carefully con ducted, in order that the deposit may be bright and as smooth as the surface of the electrotype, because the beauty of the finish attained by the conversion of the deposited iron coat into magnetic oxide of iron de pends largely on the character of the pre liminary plating. I find that about an hours suspension in this loath produces a thick enough film of iron on the surface of the electrotype to serve the purpose of the final operation. The iron-coated electrotype is (No specimens.)

then introduced into a fireproof muffle filled with an atmosphere of superheated steam at a temperature of from 1000 to 12:00 Fahrenheit. An exposure to this steam atmosphere of from five to seven minutes converts the iron coat on the surface of the electrotype into magnetic oxide of iron. Care must be exercised to so time the exposure to the steam atmosphere that the iron coat only is converted. If the exposure be continued too long, the surface of the copper beneath the iron will be oxidized also, as a consequence of which the magnetic-oxideof-iron coat or plating will lose its hold on the copper and can be rubbed off easily.

The magneticoxide-of-iron plating thus produced is very coherent, and has a steelbluish black color, very attractive to the eye. Its hard and non-corrosive qualities are well known.

My invention of the art of producing a magnetic-oxide-of-iron plating is not limited to the particular bath described, since other known iron-plating baths may be used; nor to the described means of converting the iron plating'into magnetic oxide, because the conversion may be effected by other known means-for instance, by the use of what is known as the Bower- Earff Furnace.

My invention is applicable to all articles of manufacture and objects of art in metals that are susceptible of being coated with an electro-deposit of iron, which can afterward be converted into magnetic oxide without injury to the article itself.

I am aware that metallic objectsletterpress electrotypes, for instancehave here tofore been plated with iron or steel; also, that objects of iron have heretofore been provided with a coating of magnetic oxide by a direct conversion of the surface of the iron object. I am also aware of the United States Patent No. 106,823; but I believe that I am the first to have covered metallic objeots with an electroplated coat of magnetic oxide of iron.

The resultant article of my described process is claimed in my application fora United States Patentvfiled April 30, 1885, Serial No. In testimony whereof Iaffix my signature in 10 164,024. presence of two witnesses.

I claim as my invention The art of covering a metallic object with WILLIAM H. WIN SLOW.

5 an e1ectrop1ated coat of magnetic oxide of iron, which consists in first electroplating Witnesses: the object with iron and then converting the MICHAEL EGER, plating of iron into magnetic oxide, substan- GEORGE E. HORNUNN. tially as before set forth.