US1485436A - Means for preventing occlusion of hydrogen in metal cathodes - Google Patents

Description

.Patented Mar. 4, 1924. 0.

UNITED STAT-ES 1,485,436 PATENT OFFICE.

JOSEPH SLEPIAN, OF WILKINSBUBG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC dc MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

MEANS FOR PREVENTING OCCLUSION OF HYDROGEN IN METAL CATHODES.

No Drawing.

To all whom it may comm:

Be it known that I, Josnrn SLEPIAN, a citizen of the United States, and a resident of Wilkinsbur in the oounty'of Allegheny and State of ennsylvania, have invented a new and useful Improvement in Means for Preventing Occlusion of Hydrogen in Metal Cathodes, of which the following is a specification.

My invention relates to electrolytic reactions and methods of conducting them, and it has, for its primary object, the provision of a method by which the occlusion of gases, and, particularly, of hydrogen in metallic electrodes, to any material extent is prevented.

Heretofore, for some purposes, considerable difliculty has been experienced in electro-plating steel and other ferrous metals because of the deleterious effect upon such metals occasioned by occluded gases and,

particularly, hydrogen which may have been absorbed by them during the electro-plating treatment. The primary object of my present invention, therefore, resides in the provision of a method of electro-plating ferrous bodies or articles in such manner as to prevent, to as great an extent as possible, any occlusion of gases in the metals being treated.

I have observed that, when employing metallic electrodes in a suitable electrolyte, in the nature of a cold solution, even very small currents would produce gas at the electrodes, and the electrolyte, on this account, would oifer an abnormal resistance to the passage of current. As the solution warmed up, however, I noted that the gases disappeared and that. between the temperature 0' between 30 and 35 (3., the gassing ceased and the resistance became normal, even for relatively high current densities.

In my openion, this may be accounted for by assuming that, when hydrogen is liberated, in gaseous form, from a solution, by an electric current, it cannot be returned into solution by reversals of the current, because the gas thus liberated is a non-conductor. If, however, the hydrogen ions are occluded by the metallic electrodes employed, they then act like conducting varieties of hydrogen and will return into the solution or electrolyte upon reversal of the current.

If the foregoing theory is correct, and all tests conducted by me indicate that it is, it

Application filed January 12, 1920. Serial No. 851,005.

will'be clear that gas occlusion in metallic electrodes, and, particularly, in ferrous elec' trodes, such as steel, increases rapidly with the temperature of the electrolyte and especiall(y: when such temperature approaches 30 My present invention, therefore, resides in conducting electrolytic reactions of this character under such conditions as to maintain theelectrolyte employed in a cool condition, in order that the ferrous electrodes being treated may not absorb the hydrogen or the other gases which may be given off. For example, in practising my invention, I may dispose ferrous or steel electrodes in a proper electro-plating bath or electrolyte and I may pass a sultable current between the electrodes through the bath while maintaining the bath in a cool state by any suit able means, as by the employment of cooling coils immersed in the bath. Although I do not wish to be restricted to specific details, the primary feature of my invention resides in keepin the temperature of the bath below 30 and, preferably, in keeping the bath relatively 0001.

In practising my invention, I may provide a solution of approximately 1% sodium car bonate in water and utilize electrodes of ingot iron of suitable The electrolysis may becarried out with a current density of to 10 amperes per square inch at 25 cycles A. C. The temperature is preferably maintained below 30 C.

While it is not essential, I prefer to practice my invention under a reduced pressure, as this is also beneficial in keeping the gases from going into the metallic electrodes. In view of the relatively broad scope of my invention, including, as it does, the employment of numerous characters of electrodes and electrolytic solutions, it will be apprecia-ted that no limitations are to be imposed upon my invention other than those indicated in the appended claims.

I claim as my invention 1. The method of preventing occlusion of gases in ferrous electrodes ofelectrolytic apparatus that comprises maintaining the electrolyte employed in a cool state.

2. The method of preventing occlusion of gases in iron being treated during electroplating that comprises keeping the electrolytic bath at a temperature below 30 C.

3. The method of preventing occlusion of gases in iron being treated during electroplating that comprises keeping the electrolytic bath at a temperature below 30 (3., and carrying out the operation under subls atmospheric ressure.

4. The met 0d of preventing occlusion of gases in ferrous electrodes of electrolytic apmsewwe paratus that comprises maintaining the electrolyte employed in a cool state and electrolyzing with an alternating current.

In testimony whereof, I have hereunto subscribed my name this 31st day of Decemher 1919. V

JOSEPH SLEPIAN.