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Electrolytic pickling process and its effect on the physical properties of iron and steel
804
CURREI~'T TOPICS.
[J. F. I.
,7 Riecke: Wied. Ann., 66, 376 (1898). *~Lenard, P.: Ann. d. Phys., 3, 313 (19oo). 89Thomson, J. J.: Proc. Cam. Phil. Soc., I5, 375 (191o). *°Reinganum: Phys. Zeits., 12, 575 and 666 (1911). ,1Przibram, K. : See on page 269 of Franck, loc. cir. (14). aKleemann: Phys. Zeits., 12, 9oo (I9II). 4~Langevin, M.: Ann. d. Chem. et d. Phys. (5), 8, 245 (I9O5). **Zeleny, .1. : Phil. Trans., A, I95, 193 (I9OO). ~*Przlbrarn, K.: Wien. Berichte, IIa, I17, 665 (19o8); Ibid., IIa, ii8, 665 (19o8) ; Ibid., IIa, 118, December (19o9) ; Ibid., IIa, II8, March (19o9) ; Ibid., IIa, 118, 332 (19o9). ,c Wellisch, E. 3/[. : Phil. Ma9., 34, I99, July, 1917. ,7 Franck and Hertz : Ber. d. D. Phys. Ges., 15, pp. 34, 373, 613, 19:3, and I6, pp. 12, 457, 1914•
Electrolytic Pickling Process and Its Effect on the Physical Properties of I r o n a n d Steel. J. COULSON. (Proceedings o/ the A m e r i c a n Electrochemical Society, October 3-6, I 9 1 7 . ) - - B r i t t l e n e s s of steel springs resulting from acid pickling and electroplating is a well-known phenomenon. T e m p e r e d springs which are pickled even for a few seconds in an acid bath snap when subjected to strain. Such springs, however, can be electrolytically pickled without destroying their resiliency. It is known that metals absorb gases and that the amount absorbed depends upon the nature of the gas, the condition and character of the metal, and the surrounding medium. These absorbed gases appear to have an important influence on the behavior of iron, steel, and certain alloys. Electrolytic iron is extremely brittle, due principally to occluded hydrogen, and there appears no doubt that the brittleness of steel springs a f t e r pickling is caused by the absorption of hydrogen during the ordinary pickling process. T h e effect is still more pronounced if the springs are made the cathode in an acidulated electrolyte. T o determine the embrittling effect of adsorbed hydrogen upon steel pickled in different ways, samples of steel wire were pickled chemically by simple dipping in acid, also by electrolytic pickling, using them as cathodes or as anodes. Oscillation tests on the original wires, sand blasted, and three sets treated as described, showed the chemically cleaned and the cathodically cleaned to be very brittle, while the anodically cleaned had the strength of the original samples. Similar tests were aso made with drill-rod steel, hot-rolled Bessemer, and cold rolled steel, a f t e r which mechanical tests were made as to strength, elongation, and reduction of area. T h e chemically and cathodically cleaned specimens again showed greater brittleness, which was most marked with the high-carbon steels and less marked with the soft steel.
CURREI~'T TOPICS.
[J. F. I.
,7 Riecke: Wied. Ann., 66, 376 (1898). *~Lenard, P.: Ann. d. Phys., 3, 313 (19oo). 89Thomson, J. J.: Proc. Cam. Phil. Soc., I5, 375 (191o). *°Reinganum: Phys. Zeits., 12, 575 and 666 (1911). ,1Przibram, K. : See on page 269 of Franck, loc. cir. (14). aKleemann: Phys. Zeits., 12, 9oo (I9II). 4~Langevin, M.: Ann. d. Chem. et d. Phys. (5), 8, 245 (I9O5). **Zeleny, .1. : Phil. Trans., A, I95, 193 (I9OO). ~*Przlbrarn, K.: Wien. Berichte, IIa, I17, 665 (19o8); Ibid., IIa, ii8, 665 (19o8) ; Ibid., IIa, 118, December (19o9) ; Ibid., IIa, II8, March (19o9) ; Ibid., IIa, 118, 332 (19o9). ,c Wellisch, E. 3/[. : Phil. Ma9., 34, I99, July, 1917. ,7 Franck and Hertz : Ber. d. D. Phys. Ges., 15, pp. 34, 373, 613, 19:3, and I6, pp. 12, 457, 1914•
Electrolytic Pickling Process and Its Effect on the Physical Properties of I r o n a n d Steel. J. COULSON. (Proceedings o/ the A m e r i c a n Electrochemical Society, October 3-6, I 9 1 7 . ) - - B r i t t l e n e s s of steel springs resulting from acid pickling and electroplating is a well-known phenomenon. T e m p e r e d springs which are pickled even for a few seconds in an acid bath snap when subjected to strain. Such springs, however, can be electrolytically pickled without destroying their resiliency. It is known that metals absorb gases and that the amount absorbed depends upon the nature of the gas, the condition and character of the metal, and the surrounding medium. These absorbed gases appear to have an important influence on the behavior of iron, steel, and certain alloys. Electrolytic iron is extremely brittle, due principally to occluded hydrogen, and there appears no doubt that the brittleness of steel springs a f t e r pickling is caused by the absorption of hydrogen during the ordinary pickling process. T h e effect is still more pronounced if the springs are made the cathode in an acidulated electrolyte. T o determine the embrittling effect of adsorbed hydrogen upon steel pickled in different ways, samples of steel wire were pickled chemically by simple dipping in acid, also by electrolytic pickling, using them as cathodes or as anodes. Oscillation tests on the original wires, sand blasted, and three sets treated as described, showed the chemically cleaned and the cathodically cleaned to be very brittle, while the anodically cleaned had the strength of the original samples. Similar tests were aso made with drill-rod steel, hot-rolled Bessemer, and cold rolled steel, a f t e r which mechanical tests were made as to strength, elongation, and reduction of area. T h e chemically and cathodically cleaned specimens again showed greater brittleness, which was most marked with the high-carbon steels and less marked with the soft steel.