Abstract
The dependence of the corrosion rate of a 0·06 % C steel upon the pH and chloride ion activity of solutions of hydrochloric acid at 30°–50° has been examined. A significant amount of simultaneous chemical dissolution takes place as the strength of acid is increased and this leads to anomalously high values of the Tafel parameters, and renders the Stern ‘polarisation resistance’ treatment inoperative. Additions of thiourea produce cathodic stimulation at low concentrations and general inhibition at high concentrations. The results are mterpreted in terms of thiourea dissociation to hydrosulphide ion.
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References
1.
Hoar
T. P.
, &
Holiday
R. D.
J. appl. Chem. , Lond. , 1953 , 3 , 502
2.
West
J. M.
, ibid. , 1960 , 10 , 250
3.
Chaturvedi
M. C.
, M. Met. Thesis , Sheffield University , 1962
4.
Makrides
A. C.
, &
Hackerman
N.
Ind. Engng Chem. , 1955 , 47 , 1773
5.
Anderson
G.
,
Tragardh
U.
, &
Wranglen
G.
Current corrosion research in Scandinavia’ , 1964 , p. 11 (Helsinki : Kemian Keskusliitto )
6.
Jofa
Z. A.
,
Batrakov
V. V.
, &
Huo
N. P.
Prot. Metals , 1965 , 1 , 61
7.
Sandell
E. B.
, ‘Calorimetric determination of traces of metals’ , 1944 , p. 271 (New York : Interscience )
8.
Ya
Kolotyrkin
M. , & Florianovich, G. M. , Prot. Metals , 1965 , 1 , 9
9.
Cavallaro
L.
,
Felloni
L.
,
Trabanelli
G.
, &
Pulidori
F.
2nd Int. Congr. Metallic Corros. , 1966 , p. 581
10.
Greene
N. D.
, &
Saltzman
G. A.
Corrosion , 1964 , 20 , 293t
11.
Parsons
R.
, ‘Handbook of electrochemical constants’ , 1959 (Butterworths)
12.
Jofa
Z. A.
, Eur. Symp. Corros. Inhib. Ferara, 1965, p. 151; Jofa, Z. A., et al. , Electrochim. Acta , 1964 , 9 , 1645
13.
Bockris
J. O'M.
, &
Conway
B. E.
Modern aspects of electrochemistry , No. 3 , 1964 , p. 203 (Butterworths)
14.
Bockris
J. O ‘M.
, ‘Modern aspects of electrochemistry , No. 1 , 1954 , p. 200 (Butterworths)
15.
Oakes
G.
, &
West
J M.
.in preparation; Oakes, G., Ph.D. thesis, Sheffield University , 1966
16.
Stern
M.
, J. Electrochem. Soc. , 1955 , 102 , 609 ,
17.
Brasher
D. M.
, Nature , Lond. , 1960 , 185 , 838
18.
Aiazian
E. C.
, Dokl. Akad. Nauk. SSSR , 1955 , 100 , 473
19.
Antropov
L. I.
, ‘Kinetics of electrode processes and null points of metals’ , 1959 , p. 65 (CSIR)
20.
Lorenz
W. J.
, &
Fischer
H.
Electrochim. Acta , 1966 , 11 , 1597
21.
Carassiti
V.
,
Trabanelli
G.
, &
Zuechi
F.
Eur. Symp. Corros. Inhib. Ferrara , 1965 , p. 331
22.
Putilova
I. N.
,
Balezin
S. A.
, &
Barannik
V. P.
Metallic corrosion inhibitors’ , 1960 , p. 55 (Pergamon)