Influence of the corrosion products of copper on its atmospheric corrosion kinetics in tropical...

www.elsevier.com/locate/corsci

Corrosion Science 46 (2004) 1189–1200

Influence of the corrosion products ofcopper on its atmospheric corrosion

kinetics in tropical climate

Antonio R. Mendoza a,*, Francisco Corvo a,Ariel G�omez b, Jorge G�omez c

a Corrosion Department, National Centre for Scientific Research, Ave. 25 and 158,

P.O. Box 6412, Cubanacan, Playa, Havana, Cubab Faculty of Physics, University of Havana, San Lazaro and L, 10400, Havana, Cuba

c Oil Research Centre, Washington 169, 12000, Havana, Cuba

Received 23 April 2003; accepted 26 September 2003

Abstract

In the present paper, the identification of the corrosion product phases formed on copper

under different atmospheres of Cuban tropical climate is reported. Cuprite (Cu2O), parat-

acamite (Cu2Cl(OH)3), posnjakite (Cu4SO4(OH)6 Æ 2H2O) and brochantite (Cu4SO4(OH)6)

were the main phases identified by X-ray diffraction (XRD) analysis and Fourier transform

infrared spectroscopy (FTIR).

Copper corrosion products are known to have a protective effect against corrosion.

However, a different behaviour was obtained under sheltered coastal conditions. This can be

due to the corrosion products morphology and degree of crystallisation, rather than their

phase composition. A higher time of wetness and the accumulation of pollutants not washed

away from the metal surface can also play an important role.

� 2003 Elsevier Ltd. All rights reserved.

1. Introduction

Copper is a noble metal, being stable in a part of the stability region of water in

the Pourbaix diagrams [1]. Because of its high electrical conductivity and resistance

* Corresponding author. Present address: Department of Mechanical Engineering, University of

Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.

E-mail address: [email protected] (A.R. Mendoza).

0010-938X/$ - see front matter � 2003 Elsevier Ltd. All rights reserved.

doi:10.1016/j.corsci.2003.09.014

mail to: [email protected]

1190 A.R. Mendoza et al. / Corrosion Science 46 (2004) 1189–1200

to the action of the atmosphere, it is widely used in the electrical and electronics

industries. However, the tendency to use smaller electronic components has in-

creased the corrosion risk even indoors where the levels of pollutants and moisture

are very low.

The atmospheric corrosion rate depends mainly on pollutants present in the at-

mosphere and on the time of wetness, i.e., the duration and frequency of wetting towhich metal surface are subjected [2,3], and rate at which dries. The composition,

hygroscopicity and degree of crystallisation of the corrosion products are also

functions of these parameters, and could play an important part on atmospheric

corrosion kinetics. Consequently, the phases present in the copper corrosion prod-

ucts depend on the atmosphere and exposure conditions, so that, their composition

[4] and morphology can be different indoors from outdoors. Most of the studies

about identification of copper corrosion products have been about those formed

outdoors and only a few of them have been focused on those formed indoors.Cuprite is generally the corrosion product first formed regardless of the exposure

conditions, so that it is always present on the copper surface [5–12]. Cuprite reacts

slowly with pollutants such as chloride ions, SO2 and CO2 to form basic copper salts,

provided the pH value of the surface moisture is sufficiently high [11]. In urban,

industrial and rural atmospheres, basic sulphates are the predominating compo-

nents, while in marine atmospheres are basic chlorides [11].

Other patina constituents have been reported, as particulate species, which can

accelerate copper corrosion, especially if they are not washed away from the surface(as when the metal are exposed to sheltered conditions) [11,13].

Hygroscopic corrosion products can diminish the critical relative humidity [6,14],

and influence the sorption of pollutants, so that corrosion is more probable to occur.

Once corrosion products are formed there is a decrease in the level of humidity at

which high rates of adsorption of SO2 may be observed [15]. They could also have a

catalytic effect in the oxidation of SO2, donating reactive species, such as sulphate

ions, which accelerate the corrosion [16,17].

For a long time, it has been claimed the protective action of copper patina withtime, as a result of the cuprite layer [8]. However, an increase in the copper corrosion

rate with time under sheltered coastal conditions was recently found [18]. Several

authors have reported the composition of copper corrosion products formed in

different atmospheres, but very few relate it with the corrosion kinetics. The aim of

this work is to find this relationship based on the results previously reported [18] and

the identification by XRD and FTIR of the corrosion products of copper exposed

to different atmospheres and exposure conditions in Cuban tropical climate.

2. Experimental method

Atmospheric corrosion tests were carried out at three different atmospheres (rural,urban-industrial and coastal), under different exposure conditions (outdoors, shel-

tered and ventilated shed). A detailed description of the test sites and exposure

conditions is given in a previous publication [19]. The average chloride and sulphur

A.R. Mendoza et al. / Corrosion Science 46 (2004) 1189–1200 1191

compound deposition rates, as well as the preparation method [20] of the commercial

pure copper samples (150 mm · 100 mm · 1 mm), are also given.

Duplicate samples were exposed at 45� to the horizontal, facing south, in outdoor

conditions, as well as under sheltered conditions in the rural station. In the coastal

zone, under sheltered and ventilated shed conditions, they were exposed vertically, as

well as in the urban-industrial site under sheltered conditions.The composition of the corrosion products scraped off from the exposed samples

was determined by X-ray diffraction analysis (XRD) and Fourier transform infrared

spectroscopy (FTIR).

The XRD patterns were recorded in HZG4 goniometer (Carl Zeiss, Jena)

equipped with an ENRAFNONIUS Diffractis 582 generator. The patterns were

scanned between 10� and 65� two theta with a 0.05� step and 8 s counting time using

Fe filtered Co-Ka radiation (k ¼ 1:79026 �A). The phases present were identified

using the PCPDFWIN search/match program (Version 1.30) using the PowderDiffraction File (PDF) 1997 Database. The composition of the copper corrosion

products was determined based on the strongest reflection lines in the XRD patterns,

according to the PDF.

Corrosion product samples were also analysed by FTIR. They were examined by

the KBr disk method. A portion of each corrosion product sample was pressed into

pellets, mixed with spectrally pure KBr and subjected to infrared transmission

spectroscopic analysis. Fourier transform transmission spectra in the range of 4000–

400 cm�1 were obtained using a Carl Zeiss (Bruker) spectrophotometer (modelVector 22) equipped with a DTGS detector with KBr window and a KBr beams-

plitter.

IR spectra were recorded in transmittance format at a resolution of 4 cm�1 and

were interpreted taking into account data previously reported in the literature

[5,12,21–28], as well as the XRD results obtained in this work. The characterisation

of the corrosion products has been performed, in most of the cited works, by in-

frared-reflection-absorption spectroscopy (IRAS). However, it is known that IRAS

spectra possibly shift to the high wave number region and give different shapes fromthose obtained by transmission spectra in some cases [4,5,27]. This could be the

reason for the differences in the wavenumber region observed compared with those

reported in the literature.

The remainder of the corrosion products were removed in order to determine the

corrosion rate by weight loss, according to ISO 9226 [29]. The corrosion rate values

have been already reported in a previous work [18].

3. Results

3.1. Analysis of copper corrosion products by X-ray diffraction analysis

The samples exposed in outdoor and sheltered coastal environment are charac-

terised by a surface covered with a loose powdery scale of a light bluish green colour.

However, under ventilated shed conditions the coloration assumed was reddish


brown with small greenish stains during the first 12 months, being larger after 18

months. In the urban-industrial station, under sheltered conditions, the specimens

developed a golden coloration with some black stains, and in the open air a dark

grey colour. In the case of the rural site the appearance of the outdoor corrosion

products formed was mainly grey-blue, although the inner layer was reddish,

whereas sheltered conditions yielded a brown-reddish appearance. All the coppersamples corroded uniformly, independently of the atmosphere type.

Typical diffraction patterns of corrosion products formed in the three atmo-

spheres under different exposure periods and conditions are shown in Figs. 1 and 2.

Table 1 shows the composition of copper corrosion products formed through the

whole test period under different exposure conditions, according to the XRD ana-

lysis.

As can be seen from Table 1, cuprite (Cu2O) was predominant under most of the

exposure conditions and atmospheres. Only in outdoor coastal conditions the copperbehaviour was different where paratacamite (Cu2Cl(OH)3) was the main phase.

Under these conditions posnjakite (Cu4SO4(OH)6 Æ 2H2O) was also detected, while in

industrial (both outdoors and indoors) and rural (outdoors) environments bro-

chantite (Cu4SO4(OH)6) was the basic sulphate found. Gypsum (CaSO4 Æ 2H2O) was

also identified under some of the exposure conditions tested.

It is worth noting from this table the presence of paratacamite in ventilated shed

coastal conditions, even though the chloride deposition rate is very low. Cuprite

and paratacamite were present during the entire exposure period under outdoor andindoor coastal conditions. After 18 months of exposure in the urban-industrial and

Fig. 1. XRD patterns of Cu corrosion products formed on samples exposed in the coastal site.

Fig. 2. XRD patterns of Cu corrosion products formed on samples exposed in the rural and urban-

industrial stations.

Table 1

XRD identification of copper corrosion products formed under different atmospheres during the entire

exposure period

Conditions Atmosphere type

Coastal Industrial Rural

Outdoor Paratacamite Cuprite Cuprite

Cuprite Brochantite Brochantite

Posnjakite Paratacamite Paratacamite

Gypsum

Sheltered Cuprite Cuprite Cuprite

Paratacamite Brochantite Gypsum

Paratacamite

Gypsum

Ventilated shed Cuprite – –

Paratacamite – –

The phases are ordered according to the intensity of their peaks in the XRD pattern.


rural stations, cuprite continues to be the predominant phase both outdoors and

under sheltered conditions.Atacamite [7,11,22,30–32] and paratacamite [11,30,32,33] are the compounds

commonly reported in the literature as the main constituents of copper patinas

formed in marine atmospheres. However, the former could not be found on any of

the copper samples tested in this work. Paratacamite is said to be an isomorphous


compound of atacamite to which is transformed with time. Veleva et al. [33] also

found cuprite and paratacamite as the main phases in a marine atmosphere and

noticed that cuprite changes to paratacamite with time.

It should be also noted from Table 1 that under indoor coastal conditions no

crystalline sulphate could be detected.

Brochantite, antlerite and gypsum are the most frequently identified sulphate [23];however, in this study antlerite could not be identified on any of the copper samples.

Some authors have observed that there is a critical SO2 concentration above which

brochantite does not form and existing patinated surfaces will dissolve [34]. Cuprite,

brochantite and antlerite (in a very low proportion) were detected by XRD after 14

years of outdoor exposure in rural and urban-industrial atmospheres [35].

It has been also reported that when the chloride concentration is very high,

brochantite can react with chloride ions to form basic chlorides [28,33]. The stability

of brochantite (Cu4SO4(OH)6) with respect to basic chlorides is represented by thefollowing reaction [28,33]:

Cu4SO4ðOHÞ6 þ 2Cl� () Cu4Cl2ðOHÞ6 þ SO2�4 ð1Þ

Brochantite is stable when [SO2�4 ]/[Cl�]2 P 5.5 [28]. Thus, one possible explanation

of the absence of posnjakite after 18 months could be its transformation in basic

copper chloride, due to the very high chloride deposition rate in the coastal site.

Posnjakite acts as an unstable intermediate phase in the brochantite forming process,

although it also occurs as a naturally formed mineral [22]. Brochantite is more stable

than posnjakite in basic solutions [34].

Odnevall and Leygraf [12,22] reported that in sheltered exposure conditions cu-prite and posnjakite are the main constituents in copper patina formed during rural

and urban exposures. However, they also reported that cuprite was the only iden-

tified crystalline corrosion product after 1 year of sheltered exposure in another test

program, whereas after 2 and 4 years, posnjakite and brochantite were also identi-

fied.

3.2. Analysis of copper corrosion products by IR spectroscopy

Fig. 3 shows representative spectra of copper corrosion products formed in the

coastal station under different exposure conditions and exposure time. As can beseen, significant differences are not observed between the spectra of the corrosion

products formed outdoors and those formed under sheltered conditions. In the

urban-industrial site were obtained similar results, but not in the rural station.

However, whereas strong bands around 3332 and 3440 cm�1 dominate all the spectra

in the coastal station, a band at 1105 and 625 cm�1 dominate the spectra from the

urban-industrial and rural stations, respectively. A band at 623 cm�1 is also pre-

dominant in the spectra from ventilated shed conditions (coastal station).

The bands around 3332 and 3440 cm�1 are assumed to originate from stretchingvibrations of hydroxyl groups of paratacamite, as well as from water [27,36,37]. The

small band at 1630 cm�1 is attributed to OH deformation vibration. Smaller bands

around 940 and 840 cm�1, as well as a shoulder at 985 cm�1, are also assigned to

Fig. 3. IR spectral variations with time and exposure conditions on copper exposed in the coastal site.


paratacamite [23,25], which, according to XRD results, was the main phase in the

coastal station under outdoor and sheltered conditions. In spite of the fact that the

band characteristic of sulphates (around 1100 cm�1) is observed in all the spectra of

the coastal samples, no crystalline sulphate could be found under sheltered and

ventilated shed conditions by XRD analysis. In contrast, posnjakite (Cu4SO4(OH)6 Æ2H2O) and gypsum (CaSO4 Æ 2H2O) were found outdoors after 12 and 18 months,

respectively. Under sheltered and ventilated shed conditions, sulphates could be

present below XRD detection limits.A band around 1105 cm�1 in the urban-industrial spectra (outdoors) is assigned to

brochantite, as well as those at 608, 878 and 980 cm�1 [23]. However, in the spectra

of the sheltered samples a strong peak around 1140 cm�1, characteristic of gypsum, is

observed after 18 months of exposure, and could influence the mentioned sulphate

bands. The latter is in agreement with XRD data, in that gypsum was detected under

sheltered conditions, but not outdoors. It has been noted that rain exposure delayed

the formation of sulphate-containing corrosion products [38]. Several authors have

reported the basic sulphates as the predominating phase in this type of atmosphere[7,11,22,30–32,39].

In the rural station a peak at 625 cm�1 from cuprite dominates the spectra both

outdoors and indoors, consistent with XRD data. The IR spectra from synthetic

cuprite showed a predominant band at 620 cm�1. Absorption bands at 625 [28], 625–

610 [40], 620–610 [25] and 615 cm�1 [24] have been assigned to cuprite. A strong


band at 1100 cm�1 is also observed in the spectra from sheltered conditions, although

basic copper sulphate was not found by XRD; however, gypsum was detected after

12 months of exposure under these conditions.

As can be seen from Table 2, bands characteristics of brochantite are also iden-

tified under outdoor rural conditions, mainly after 12 and 18 months. Bands char-

acteristics of basic chlorides are not evident in the spectra, even though paratacamitewas detected by XRD. However, a split approximately at 3440 and 3350 cm�1,

probably due to the presence of this phase, is observed in the spectra.

Some authors have assumed an IRAS peak around 1107 cm�1 to be representative

of a cupric sulphate, whereas splitting of the peak into two peaks at around 1070 and

1120 cm�1 is representative of a basic copper sulphate [22,38], as it was showed

above for outdoor conditions. Odnevall and Leygraf [22] noted that the cuprite

formation is followed by the formation of a noncrystalline copper sulphate phase,

which gradually transforms after short exposure periods into crystalline posnjakite,the hydrate form of brochantite.

All IR spectra showed peaks approximately below 500 cm�1, which is charac-

teristic of Cu–O bending and could be due to the different phases present in the

corrosion products, and in the region 1500–1380 cm�1, being more or less intense

depending on the exposure conditions. At the present time, it is not possible to assign

the last bands to a particular compound, since other phases may also be present,

even though they were not identified by XRD. Absorption bands in this region have

been reported for basic carbonates [23], nitrates [23,26], and aliphatic compounds[35]. However, it has been stated that the conditions in the atmosphere would not

favour the formation of basic copper carbonate, for the H2CO3 content in the water

film would only be about 10�5 mol/l in equilibrium with the air, although unex-

pectedly it is sometimes found in practice [11].

Table 2

Main absorption bands (cm�1) observed in the IR spectra of the copper corrosion products and phases

assigned

Conditions Atmosphere type

Coastal Industrial Rural

Outdoor Paratacamite (3440, 3332,

940, 840, 985)

Brochantite (1105, 980,

878, 608)

Cuprite (625)

Posnjakite, Gypsum (1110,

604)

Cuprite (625)


972, 872, 782)

Cuprite (625)

Sheltered Paratacamite (3440, 3332,

940, 840, 985)


878, 608)

Cuprite (625)

Cuprite (625) Gypsum (1140)

Gypsum (1140)

Cupric sulphate (1110) Cuprite (625)

Ventilated

shed

Cuprite (623) – –

Paratacamite (3440, 3332,

940, 985)

Cupric sulphate (1110)


Table 2 shows a resume of the main bands observed in the spectra of copper

corrosion products and the phases identified.

4. Discussion

Previous results showed a generally decrease in the copper corrosion rate in the

rural and urban-industrial stations. This can be due to an improvement of the

protective properties of the corrosion products. However, in the coastal station

under sheltered and ventilated shed conditions the corrosion rate increased with time[18].

The presence of paratacamite under these coastal conditions may explain the

increase in the corrosion rate due to its hygroscopic character. This provokes an

easier wetting of the surface, which results in a decrease of the critical relative hu-

midity, and a larger time of wetness because of the absence of sunlight.

It is well known that the copper corrosion is extremely dependent on the rela-

tive humidity [7]. Several investigators have demonstrated the rate of reaction

dependence of moisture between copper and air pollutants [41]. Cramer and Mc-Donald [3] found that moisture is more readily available on corroded copper sur-

faces from capillary condensation and from the hydrophilic nature of their corrosion

products, than on non corroded surfaces. However, observations of copper roofs

indicate that patina grows preferentially in areas washed by rain and areas that

experience water films thicker than those associate with dew or high relative hu-

midity [34].

It has been also reported that the repeated dissolution–reprecipitation processes

made a slow formation of sulphate containing corrosion products possible due tolong dry and wet periods [22].

The bronze disease is related to the presence of copper chlorides and it is con-

sidered a cyclic and autocatalitic (self-feeding) chemical process [23]. An increase in

the electrolyte film pH promotes oxygen corrosion in the presence of chlorides, to

which copper is susceptible.

It is noteworthy that the difference in the corrosion behaviour between outdoor

and sheltered coastal exposure is observed despite the fact that the corrosion product

composition in both exposure conditions are practically the same.This may indicatea more important role of the morphology and degree of crystallisation of the cor-

rosion products on the corrosion rate than their phase composition, at least during

the exposure period of the test (18 months) and particularly in coastal environments.

This statement is based on the fact that the corrosion products are formed mainly

under the presence or absence of rainfall and sunshine. On the one hand, due to the

absence of rainfall under sheltered conditions, the pollutants are not washed away

from the metal surface, and may act for a longer time. On the other hand, it is

possible that a higher time of wetness could exist due to the absence of sunshine, as itwas proposed previously [18]. According to ISO 9223 [42], the presence of hygro-

scopic salts may increase substantially the time of wetness on marine sheltered

surfaces, where chloride ions are deposited.


Nairn et al. [43] also concluded that the corrosion rates for copper alloys can be

very dependent on the morphology of the corrosion products on the copper surface.

They confirmed that corrosion products of the same composition (Cu2O) could give

higher corrosion rates when they do not dry out than when they do. These rapid

corrosion rates have been associated with corrosion products in the form of a gel

rather than an oxide [42]. It has been reported that the amorphous ferric oxyhy-droxide acts as a protective rust against atmospheric corrosion of steels [43].

The abovementioned could be also the reasons for the higher corrosion rates

under ventilated shed conditions than outdoors after 12 months of coastal exposure.

It must be recalled that under these conditions the corrosion products are mostly

constituted by cuprite, which is very different from outdoors. Cuprite is an electri-

cally conducting compound and is known to play a decisive role in the protectiveness

of corrosion layers on copper [44,45]. The electrolyte film on the surface is then

considered to be in contact with cuprite (no copper substrate) and further oxidationoccurs via the following reaction [34]:

Cu2Oþ 2Hþ ! 2Cu2þ þH2Oþ 2e� ð2Þ
Precipitation of brochantite from the electrolyte resulted from an increase in pH,
which it is attributed to both the anodic oxidation of cuprite (increase in cupric ion

concentrations) and the cathodic reduction of oxygen to produce OH� ions via the

following reaction [34]:

O2 þ 2H2Oþ 4e� ! 4OH� ð3Þ
Another detail noted in this work was the higher corrosion rate in the rural station
under sheltered conditions, than in the urban-industrial atmosphere during the entire

exposure period. Odnevall and Leygraf [12] noticed that cuprite formation is much

faster in the rural than in the urban site, mainly due to the higher relative humidity

and despite lower concentrations of SO2 and NO2 in the rural site. This evidencesthat initial weathering conditions have a significant influence on atmospheric cor-

rosion rates of copper. It is well known that high relative humidities and tempera-

tures enhance the copper corrosion in rural atmospheres [9]. These authors

concluded that the fast formation rate of cuprite retards the formation of posnjakite

and could retard the subsequent formation of brochantite [12]. Fitzgerald et al. [34]

found that cuprite oxidation is the rate-controlling step for brochantite or posnjakite

precipitation within the aqueous layer.

5. Conclusions

The main phases present in copper corrosion products formed in Cuban tropical

climate were: cuprite (Cu2O), paratacamite (Cu2Cl(OH)3), posnjakite (Cu4SO4(OH)6 Æ2H2O) and brochantite (Cu4SO4(OH)6), depending on the atmosphere type and ex-posure conditions. In the coastal site outdoors and under sheltered conditions, pa-

ratacamite was the main phase, whereas under ventilated shed conditions cuprite was

predominant. In the urban-industrial, both outdoors and under sheltered conditions,


brochantite was predominant, as well as in the rural station outdoors. Under sheltered

rural conditions cuprite was the predominating phase. Gypsum (CaSO4 Æ 2H2O) was

also identified among the corrosion products, mainly under sheltered conditions.

At very high concentrations of chloride ions, the transformation of basic copper

sulphates in basic chlorides is possible to occur, as a result of their chemical reaction.

The highest corrosion rate values observed in the coastal site under sheltered andventilated shed conditions, as well as their increase with exposure time, could indi-

cate a major role of the corrosion products morphology and degree of crystallisation

than their phase composition. A longer action of pollutants and a higher time of

wetness under these conditions, as well as the hygroscopicity of some copper com-

pounds can also influence the corrosion rate.

Acknowledgements

The authors want to thank to Dr. Carmen Haces for her help in the interpretation

of IR spectra and XRD data, and for numerous stimulating discussions.

References

[1] M. Pourbaix, Atlas of electrochemical equilibria in aqueous solutions, Second English Edition,

NACE, 1974.

[2] S. Feliu, M. Morcillo, S. Feliu Jr., Corros. Sci. 34 (1993) 415–422.

[3] S.D. Cramer, L.G. McDonald, ASTM-STP 1000, ASTM, Philadelphia, PA, 1990, pp. 241–259.

[4] D. Persson, C. Leygraf, J. Electrochem. Soc. 142 (1995) 1459–1468.


[6] M. Morcillo, S. Feliu, Mapas de Espa~na de corrosividad atmosf�erica, Programa CYTED, 1993, pp. 3,

142.

[7] UN/ECE International co-operative programme on effects on materials, including historic and

cultural monuments. Report No. 11, June 1993.

[8] A. Atrens et al., Composition and structure of copper patinas, in: Proceedings of 13th International

Corrosion Congress, Melbourne Australia, November 1996.

[9] Corrosi�on y protecci�on de metales en las atm�osferas de Iberoam�erica. Parte I.––Proyecto MICAT,

XV.1/CYTED, Ed. M. Morcillo et al., 1998, pp. 547–582.

[10] M. Morcillo et al., Atmospheric corrosion in Ibero-America. in: Proceedings of 13th International


[11] V. Kucera, E. Mattsson, Atmospheric corrosion, in: F. Mansfeld (Ed.), Corrosion Mechanisms,

Marcel Dekker, Inc., New York, 1987, pp. 211–284.

[12] D. Odnevall, C. Leygraf, The atmospheric corrosion of copper––a multianalytical approach, in:

Proceedings of 13th International Corrosion Congress, Melbourne Australia, November 1996.

[13] H. Guttman, Atmospheric, weather factors in corrosion testing, Atmospheric Corrosion, John

Wiley & Sons, Inc., 1982.

[14] R.E. Lobnig et al., J. Electrochem. Soc. 143 (1996) 1539–1546.

[15] P.J. Sereda, ASTM-STP 558, ASTM, Philadelphia, PA, 1974, pp. 7–22.

[16] R. Ericsson, B. Heimler, N.-G. Vannerberg, Werk. Korr. 24 (1973) 207–209.

[17] T. Sydberger, R. Ericsson, Werk. Korr. 28 (1977) 154–158.

[18] A.R. Mendoza, F. Corvo, Corros. Sci. 42 (2000) 1123–1147.

[19] A..R. Mendoza, F. Corvo, Corros. Sci. 41 (1999) 75–86.


[20] ISO 8407:1991, Corrosion of metals and alloys––Removal of corrosion products from corrosion test

specimens.


[22] I. Odnevall, C. Leygraf, J. Electrochem. Soc. 142 (1995) 3682–3689.

[23] M. Matteini, A. Moles, C. Lalli, Stud. Conserv. 22 (1984) 18–24.

[24] F.F. Bentley et al., Infrared Spectra and Characteristic Frequencies 700–300 cm�1, John Wiley &

Sons, Inc., 1968.

[25] J.J. G�omez, Ph.D. Thesis, Oil Research Centre, Havana, 2000.

[26] Y. Fukuda et al., J. Electrochem. Soc. 138 (1991) 1238–1243.

[27] T. Sasaki et al., In situ IR-RAS investigation of surface layers initially formed on copper and low

carbon steel in nitrogen or air containing water vapor and SO2, in: Proceedings of 13th International


[28] M.E.M. Almeida, M.G.S. Ferreira, Corros~ao Atmosf�erica, 1997.

[29] ISO 9226:1992, Corrosion of metals and alloys––Corrosivity of atmospheres––Determination of

corrosion rate of standard specimens for the evaluation of corrosivity.

[30] A. Galdo et al., An�alisis de fases de patinas de cobre formadas en el clima tropical h�umedo de Cuba,

Proc. I Simposio Internacional de Corrosi�on y Tropicalizaci�on, Havana, May 9–12, 1990.

[31] T.E. Graedel, Corros. Sci. 27 (1987) 721–740.

[32] E. Mattsson, R. Holm, Atmospheric corrosion of copper and its alloys. Atmospheric Corrosion, John

Wiley & Sons, Inc., 1982, pp. 365–382.

[33] L. Veleva et al., Electrochim. Acta 41 (1996) 1641–1646.

[34] K.P. Fitzgerald et al., Corros. Sci. 40 (1998) 2029–2050.

[35] L. N�u~nez, Ph.D. Thesis, National Centre for Scientific Research, Havana, 2001.

[36] A.K. Neufeld, I.S. Cole, Use of FTIR to study surface changes on metals in the early stages of

degradation, in: Proceedings of 13th International Corrosion Congress, Melbourne Australia,

November 1996.

[37] I.S. Cole et al., Changes in surface energy and wettability of metal surfaces exposed to controlled

environments, in: Proceedings of 13th International Corrosion Congress, Melbourne Australia,

November 1996.

[38] I. Odnevall, C. Leygraf, Corros. Sci. 39 (1997) 2039–2052.

[39] R. Ericsson, T. Sydberger, Werk. Korr. 28 (1977) 755–757.

[40] R.E. Lobnig et al., J. Electrochem. Soc. 141 (1994) 2935–2941.

[41] R. Schubert, S.M. D’Egidio, Corros. Sci. 30 (1990) 999–1008.

[42] ISO 9223:1992, Corrosion of metals and alloys––Corrosivity of atmospheres––Classification.

[43] J. Nairn, K. FitzGerald, A. Atrens, Met. 95, Atmospheric corrosion of copper, Actes Conf. Int.

Conserv. Met. (1995) 86–88.

[44] M. Yamashita et al., in: 7th International Symposium on Passivity of Metals and Semiconductors,

Clausthal, Germany, August 21–26, 1994.

[45] J.L. Crolet, N. Thevenot, S. Nesic, Corros. NACE 54 (1998) 194–203.

Influence of the corrosion products of copper on its atmospheric corrosion kinetics in tropical...

Documents

Transcript of Influence of the corrosion products of copper on its atmospheric corrosion kinetics in tropical...