effect of nickel content on the corrosion resistance of iron...

Research ArticleEffect of Nickel Content on the CorrosionResistance of Iron-Nickel Alloys in ConcentratedHydrochloric Acid Pickling Solutions

Nabeel Alharthi12 El-Sayed M Sherif13 Hany S Abdo14 and S Zein El Abedin3

1Center of Excellence for Research in Engineering Materials (CEREM) Advanced Manufacturing Institute (AMI)King Saud University PO Box 800 Al-Riyadh 11421 Saudi Arabia2Mechanical Engineering Department King Saud University PO Box 800 Al-Riyadh 11421 Saudi Arabia3Electrochemistry and Corrosion Laboratory Department of Physical Chemistry National Research CentreEl-Behoth St 33 Dokki Cairo 12622 Egypt4Mechanical Design and Materials Department Faculty of Energy Engineering Aswan University Aswan 81521 Egypt

Correspondence should be addressed to El-Sayed M Sherif esherifksuedusa

Received 23 March 2017 Revised 11 May 2017 Accepted 24 May 2017 Published 22 June 2017

Academic Editor Simon C Potter

Copyright copy 2017 Nabeel Alharthi et alThis is an open access article distributed under the Creative CommonsAttribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

The effect of Ni content on the resistance against corrosion of Fe-36 Ni and Fe-45 Ni alloys in 1M hydrochloric acid picklingsolution was reported Various electrochemical and spectroscopic techniques such as potentiodynamic cyclic polarization (CPP)open-circuit potential (OCP) electrochemical impedance spectroscopy (EIS) potentiostatic current-time (PCT) and scanningelectron microscopy (SEM) and energy dispersive spectroscopy (EDS) have been employed CPPmeasurements indicated that thecorrosion current and corrosion rate recorded lower values for the alloy that had higher nickel content OCP curves proved that thepresence of high Ni content shifts the absolute potential to the positive potential direction EIS results revealed that the surface andpolarization resistances were much higher for the alloy with higher Ni content PCT curves also showed that the absolute currentswere lower for Fe-45 Ni alloy All results were in good agreement with others and confirmed clearly that the corrosion resistancein HCl solutions for Fe-45 Ni alloy was higher than that obtained for Fe-45 Ni alloy

1 Introduction

Iron-nickel alloys have been widely used in the industrybecause of its many good characteristics [1ndash4] These alloyshave unique magnetic properties good mechanical proper-ties and low thermal expansion coefficient at lower tem-peratures Due to their high corrosion and heat resistancesespecially those that have the nickel content in the range of36 to 46 they represents one of the most widely usedsuperalloys with a broad variety of applications For exampleInvar alloy (64 Fe-36 Ni) has the lowest expansion of theFe-Ni alloys [5ndash8]

It has been reported that the iron-nickel alloys haveexcellent corrosion resistance in oxidizing solutions [9ndash12]where the increase of Ni content in the alloy increases itscorrosion resistance Several researchers [10ndash15] have studied

the corrosion and corrosion mitigation of iron-nickel alloysin different aggressive media Jinlong et al [10] have reportedthe corrosion resistance of coarse grained and nanocrys-talline Ni-Fe alloys in NaCl solutions and proton exchangemembrane fuel cell environment They found that the coarsegrained Ni-Fe alloys possessed higher corrosion resistancethan the nanocrystalline alloys and this was due to the morecompact passive films formedon the surface of coarse grainedNi-Fe alloys Raman spectroscopy results indicated thatmanynanocrystalline boundaries were found in the Ni-Fe alloysthat activated the diffusion of nickel which lead to theformation of more nickel oxides and nickel hydroxides [10]Gehrmann et al [12] have investigated the corrosion behaviorof different iron-nickel alloys that have between 35wt and82wt of nickel in a humidity test between 25∘C and 80∘CThey found that the presence of higher nickel percent in the

HindawiAdvances in Materials Science and EngineeringVolume 2017 Article ID 1893672 8 pageshttpsdoiorg10115520171893672

2 Advances in Materials Science and Engineering

Table 1 Corrosion data obtained from the polarization curves for Fe-36 Ni and Fe-45 Ni in 1M HCl solutions

Alloy Corrosion parameter120573119888Vdecminus1 119864CorrV 120573119886Vdecminus1 119895Corr120583Acmminus2 119877119901Ωcm2 119877Corrmpy

Fe-36 Ni 0135 minus0475 0035 550 2197 1944Fe-45 Ni 0100 minus0248 0048 20 7050 0728

alloy improves its corrosion resistance [12] Another studyon the corrosion behavior of various iron-nickel alloys insulfuric acid solution using potentiodynamic polarizationtechnique has also been reported [13] For iron-nickel alloyscontaining up to 50 Ni a preferential dissolution of irontakes place and the percentage of iron controls the dissolutionprocess of the alloy It has been reported [14] that a toplayer of FeNi3 is formed for iron-nickel alloys that have morethan 40 iron in the alloy This was confirmed throughstudying the electrochemical corrosion behavior of differentFe-Ni alloys starting from 0 20 40 60 and 80 Niin sulfuric acid solution [14] Moreover the corrosion ratedecreases as the content of Ni increases in the alloy

This work aims at reporting the corrosion behavior of Fe-36 Ni and Fe-45 Ni alloys in concentrated hydrochloricacid (1M HCl) pickling solutions and understanding theeffect of increasing nickel content on the corrosion resistanceof the iron-nickel alloys For the best of our knowledgethe corrosion behavior of these alloys in hydrochloric acidsolutions has not been reported in the literature beforeThe study was carried out using various electrochemicaltechniques These methods included the use of potentiody-namic cyclic polarization open-circuit potential impedancespectroscopy and the change of the potentiostatic currentwith time at 0150V (AgAgCl) The corroded surfaces ofthe two nickel alloys after being immersed in 1M HClsolutions for 96 h were investigated using SEM and EDS Itwas expected that the alloy with high nickel content wouldshow better corrosion resistance due to the formation ofthicker oxides on the surface of the alloy protects it frombeing easily corroded

2 Materials and Methods

Two iron base alloys containing 36 Ni and 45 Ni with lessthan 1 of Mn + Si + C are named as Fe-36 Ni and Fe-45Ni alloys respectively These alloys have a cylindrical shapewith 60mm diameter and were purchased from Goodfellow(Ermine Business Park Huntingdon England PE29 6WR)Hydrochloric acid (HCl 32) was obtained fromMerck andwas used as received to prepare 1M concentration of theacid solution An electrochemical cell with three-electrodeconfiguration that accommodates for 300 cm3 was used toperform all electrochemical measurements The Fe-36 Niand Fe-45 Ni alloys were used as the working electrodesA silversliver chloride (AgAgCl) electrode was employed asthe reference electrode A Pt sheet was the counterelectrodein all electrochemical tests Only one surface of the iron-nickel electrodes were exposed to the electrolytic solutionwith 06 cm diameter and an area of 0283 cm2The surface ofthe iron-nickel alloys was polished and ground before being

immersed in the electrolytic solutions and performing theelectrochemical measurements as reported earlier [14ndash16]

All electrochemical measurements were performed usingan Autolab workstation (Metrohm Utrecht Netherlands)The CPP experiments were performed by scanning thepotential of the iron-nickel alloys in the hydrochloric acidtest solution from minus1200V in the positive direction to 080V(AgAgCl) at a scan rate of 0003Vs as has been reportedin our previous study [17] The EIS experiments were carriedout at the OCP after immersing the iron-nickel alloys aftertheir immersion in 1M HCl solutions for 2400 s The rangeof the frequency for the EIS was scanned from 100KHz to100mHz using an AC wave of plusmn5mV peak-to-peak overlaidon a DC bias potential The impedance data were collectedat a rate of 10 points per decade change in frequency usingPowersine software The change of the chronoamperometriccurrent for the iron-nickel electrodes versus time at 0150Vversus AgAgCl was applied for 3600 s after immersing thetested alloys in 1M HCl for 2400 s All electrochemical testswere carried out in triplicate and good reproducibility wasobserved All measurements were carried out on a fresh sur-face of the alloy with a new portion of the test solution SEMmicrographs and EDS profiles were obtained for the surfaceof the alloys after 96 hours of immersion in 1MHCl solutionsFor this purpose we used a scanning electron microscopewith an attached energy dispersive spectroscopy (JEOL)

3 Results and Discussion

31 CPP Measurements The cyclic potentiodynamic polar-ization (CPP) technique is a powerful method to obtainimportant information about the corrosion parameters ofmetals and alloys in corrosive media [18ndash23] Figure 1 showsthe CPP curves obtained for iron (1) Fe-36 Ni and (2)Fe-45 Ni immersed in 10M HCl solutions for 2400 sbefore measurements The values of cathodic Tafel (120573119888)slope corrosion potential (119864Corr) anodic Tafel (120573119886) slopecorrosion current density (119895Corr) polarization resistance (119877119901)and corrosion rate (119877Corr) that were obtained from the CPPcurves are depicted in Table 1 where the values of 119895Corr and119864Corr were obtained from the extrapolation of anodic andcathodic Tafel lines located next to the linearized currentregions [24ndash28] The values of 119877119901 were obtained from thepolarization curves using the following equation as reportedin the previous studies [24ndash28]

119877119901 = 1119895Corr (12057311988812057311988623 (120573119888 + 120573119886)) (1)

Advances in Materials Science and Engineering 3

minus09 minus06 minus03 00 03 06 09minus12E (V) (AgAgCl)

10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)

(a)

10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)


(b)

Figure 1 Cyclic potentiodynamic polarization curves obtained for (1) Fe-36 Ni and (2) Fe-45 Ni alloys in 1M HCl solutions

Moreover the values of corrosion rate (119877Corr) were obtainedas follows [25]

119877Corr = 119895Corr (119896119864119882119889119860 ) (2)

Here 119896 is a constant which defines the units for the rateof corrosion (the value of 119896 is 128800 milli-inches (amp cmyear))119864119882 is the equivalent weight in gramsequivalent of thetested alloys (the value of119864119882 is 2248 for Fe64Ni36 and 2344for Fe55Ni45) 119889 is the density in gcmminus3 (819 for Fe64Ni36and 829 for Fe55Ni45) and119860 is the area of electrode in cm2

It is well known that the cathodic reaction for metals andalloys in concentrated acid solution is the hydrogen evolutionreaction so the cathodic reaction for the nickel alloys in 1MHCl can be expressed by the following reaction

2H+ + 2eminus = H2 (3)

While the anodic reaction at this condition is the dissolu-tion of iron from the surface of the alloy as per the followingequation [26]

Fe = Fe2+ + 2eminus (4)

This dissolution reaction explains the abrupt increase ofcurrent with increasing the applied potential in the anodicbranch For the anodic side of Fe-36 Ni alloy (Figure 1(a))the current increased followed by a rapid decrease beforeabruptly increasing again till themost positive applied poten-tial The forward anodic side for the second alloy Fe-45Ni shows fast increase of currents with increasing potentialwithout showing any passivation as that recorded for Fe-36Ni alloy The first increasing in the current values was due to

the dissolution of iron (see (2)) while its decreasing (for Fe-36 Ni alloy) was due to the formation of an oxide film asfollows

Fe + 12O2 +H2O = Fe (OH)2 (5)

3Fe (OH)2 + 12O2 = Fe3O4 + 3H2O (6)

It has been reported [26 29] that the formation ofiron oxide films gives the surface some protection againstcorrosion After dissolution of this oxide film the currentincreased again till the highest positive value of the appliedpotential Moreover the values of the corrosion parameterslisted inTable 1 revealed that the uniformcorrosion of Fe-45Ni alloy in 1M HCl solution is much lower than its intensityfor Fe-36 Ni alloy where the values of 119895Corr and 119877Corr werevery low as well as the value of 119877119875 was very high for Fe-45Ni alloy as can be seen from Table 1 Also 119864Corr recorded lessnegative value for Fe-45 Ni alloy minus0248V while the valueof 119864Corr was more negative for Fe-36 Ni alloy

Upon reversing the applied potential in the backwarddirection the value of the obtained current increases com-pared to those values obtained in the forward direction forboth alloys It is noted also that the values of current andthe hysteresis loop obtained for Fe-36 Ni alloy were muchhigher than those obtained for Fe-45Ni alloyThis indicatesthat the iron-nickel alloys under investigations suffer pittingcorrosion and the intensity of pitting is lower for Fe-45 Nialloy This was confirmed by the small area of the hysteresisloop obtained for Fe-45 Ni compared to that seen for Fe-36 Ni alloy The measured CPP results along with thecalculated data thus suggested that the alloy with highernickel content Fe-45 Ni has higher resistance againstuniform as well as pitting corrosion than the alloy with low


(1)

(2)

5 10 15 20 25 30 35 400t (min)

minus045

minus040

minus035

minus030

minus025

minus020

E (V

) (A

gA

gCl)

Figure 2 Change of the open-circuit potential with time for (1) Fe-36 Ni and (2) Fe-45 Ni alloys in 1M HCl solutions

nickel content Fe-36 Ni in 1M HCl solutions at the sameconditions

32 OCP and SEMEDS Investigations Thechange of the freepotential OCP with time for (1) Fe-36 Ni alloy and (2)Fe-45 Ni alloy in the freely aerated 1M HCl solutions isdepicted in Figure 2 The initial potential of the Fe-36 Nialloy (curve (1)) recorded almost minus0408V versus AgAgCland slightly shifted towards the less negative direction withtime The value of OCP for the Fe-36 Ni alloy after 2400 simmersion in the acid solution recorded circaminus0380V whilethe initial potential for the Fe-45 Ni alloy (curve (2)) wasalmost minus0285V which is less negative than that recorded forthe Fe-36 Ni alloy Increasing the immersion time led tofurther shifts in the less negative direction to record aboutminus0212V at the end of the run The more negative initialpotential obtained for Fe-36 Ni alloy is probably due to thecorrosivity of the acid solution which dissolves the surface ofthe alloy The shift of potential in the less negative directionresulted from the formation of a thin layer of corrosionproducts that partially decreases the attack on the surface ofthe alloy by blocking some of its exposed areas The positivepotential difference between the two alloys is probably due tothe higher ability of Fe-45 Ni alloy in developing a thickerlayer of corrosion products which retains a higher corrosionresistance for the Fe-45 Ni alloy compared to Fe-36 Nialloy

In order to see the morphology of the surface as well asthe elemental analysis for the components on the surface ofthe alloys after its exposure for long immersion time in theacid test solution SEMEDS investigations were carried outFigure 3 displays (a) SEM micrograph for the surface of theFe-36 Ni alloy after its immersion in 1M HCl solutions for96 h and (b) the corresponding EDS profile analysis shownin the SEM image Figure 4 also depicts the SEMmicrograph(a) and the EDS spectra (b) for the surface of the Fe-45Ni alloy after its immersion in 1M HCl solutions for 96 h Itis seen from Figure 3(a) that the surface looks smooth andhomogeneous with a thin layer of corrosion products withsome deposits This indicates that the alloy suffers moderateuniform corrosion due to the corrosiveness attack of the acidsolution towards the surface without any indications on theoccurrence of localized corrosion The weight percentages

(wt) of the elements found on the surface were as follows4988wt iron 3917 wt nickel 0489wt oxygen and0606wt carbon The low percentage of iron and thehigh percentage detected for nickel compared to its originalpercentages in the alloy indicate that the dissolution of thealloy took place via the dissolution of Fe as mentionedbefore in (2) The presence of oxygen also indicates that thecorrosion product layermay contain some oxides such as FeOand Fe2O3 which may give some protection to the surface ofthe alloy

The SEM image shown in Figure 4(a) for the surfaceof Fe-45 Ni alloy exhibits thicker corrosion product layercompared to the corrosion products shown in Figure 3(a) forFe-36 Ni alloy This explains the reason why the potentialof Fe-45 Ni alloy shifts towards the positive direction andshows less negative values than those obtained for Fe-36 Nialloy The elements found on the surface of the alloy shownin Figure 4(a) and represented by the EDS spectra depictedin Figure 4(b) recorded 2644wt iron 1423 wt nickel1538 wt oxygen and 4394wt chlorine Here the verylow percentages of iron and nickel compared to their valuesin the alloy before their exposure to the acid solution arebecause of the formation of thick layer of corrosion productsThis layer fully covers the surface of the alloy leading toits protection and hiding the original surface of the alloyunderneath the corrosion products The high percentages ofthe detected oxygen confirm that the formed layer on thesurface of the alloy has some oxide films The presence ofthese oxides increases the passivity of the alloy as well asits corrosion resistance against the harsh effect of the acidsolution towards the surface of the alloy Therefore it isbelieved that the formed layer of corrosion products perhapscovers the whole surface of the alloy and decreases theaggressiveness attack of the acidmolecules on it and confirmsthe data obtained by polarization and OCP measurementsthat Fe-45Ni alloy hasmore corrosion resistance comparedto the alloy with lower nickel Fe-36 Ni

33 PCT Measurements Potentiostatic current-time (PCT)technique has been successfully employed to report the effectof corrosive media on the corrosion particularly pitting ofmetals and alloys [14ndash16 26] Here we used the PCTmethodto understand the effect of increasing nickel from 36 to45 on the corrosion of the tested iron-nickel alloys in10Mhydrochloric acid pickling solution Figure 5 depicts thecurrent-time behavior of (1) Fe-36 Ni and (2) Fe-45 Nialloys after their immersion in the acid solutions for 2400 sbefore stepping the potential to 0150V versus AgAgCl Thecurrent that was recorded for Fe64Ni36 alloy Figure 5 (curve(1)) showed abrupt increase from sim88mAcm2 upon theapplication of the potential to circa 98mAcm2 in the first200 seconds This increase of current has resulted from apartial dissolution of the corrosion product layer that mighthave formed on the surface during the immersion of the alloybefore applying the anodic potential Prolonging the time ofthe applied potential after the first 200 seconds and till the endof the run has resulted in rapid and continuous decreasing inthe current values This is perhaps due to the thickening ofa formed layer of corrosion products on the surface of the


(a)

Fe

Fe

FeNi

Ni

Ni

O

C

0 2 4 6 8

(b)

Figure 3 (a) SEM micrograph for the surface of the Fe-36 Ni alloy after its immersion in 1M HCl solutions for 96 h and (b) thecorresponding EDS profile analysis shown in the SEM image

(a)

0 2 4 6 8

(b)


(2)

(1)

60

70

80

90

100

j(m

Acm

minus2)

300 600 900 1200 1500 18000t (s)

Figure 5 Chronoamperometric curves obtained for (1) Fe-36Ni and (2) Fe-45 Ni immersed in 1M HCl solutions for 2400 sfollowed by stepping the potential to +0150V versus AgAgCl

alloy which protects the surface from being attacked by theaggressiveness action of the acid solutions

On the other hand the initial current recorded lowervalue (sim77mAcm2) for Fe-45 Ni alloy that value increasesin the first 150 seconds to circa 85mAcm2 The currentthen decreased with the increase of time till the end of theexperiment Here the initial increase of current is due tothe sudden application of the active potential as well as thedissolution of some of the corrosion products which wereformed during the immersion of the alloy in the solutionbefore applying the potential while the continuous decreaseof current with time was due to the ability of the nickel alloyto develop a protective layer that has iron oxides this layer


Table 2 Electrochemical impedance spectroscopy parameters obtained for Fe-36 Ni and Fe-45 Ni alloys after their immersions in 1MHCl solutions

AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)

Figure 6 Nyquist plots obtained for (1) Fe-36 Ni and (2) Fe-45Ni alloys in after their immersion for 2400 s in 1M HCl picklingsolutions

isolates the surface from being in real contact with the acidsolution and thus prevents its corrosion It is seen thus thatthe absolute currents recorded for Fe-45 Ni alloy are lowerthan those values obtained for Fe-36Ni alloy over thewholetime of the experiment which reveals that Fe-45 Ni alloyshows more corrosion resistance than Fe-36 Ni one whenexposed to the acid solution Moreover the change of currentwith time for these alloys confirms that thesematerials do notsuffer pitting corrosion at this condition

34 EIS Measurements Electrochemical impedance spec-troscopy (EIS) investigations have been widely used toreport the kinetic parameters for the electron transfer at thematerialssolution interface [26ndash30] We have successfullyemployed this method to investigate the corrosion andcorrosion protection of different metals and alloys in variouscorrosive media [26ndash33] Typical Nyquist plots obtained forironnickel alloys (a) Fe-36Ni and (b) Fe-45Ni after theirimmersion for 40 in 1M HCl are shown in Figure 6 TheNyquist plot obtained for Fe-36 Ni alloy shows one smallsemicircle followed by a short segment And the Fe-45 Nialloy depicted only one wider semicircle with higher values ofboth real and imaginary resistances The smaller diameter ofthe semicircle obtained for Fe-36 Ni alloy indicates that thealloy has low corrosion resistance as a result of the chlorideions attack The appearance of the segment following the

RP1

RP2

RS

Cdl

Q

Figure 7The equivalent circuit model used to fit EIS data shown inFigure 6

semicircle reveals that the surface forms a corrosion productlayer that protects the surface from further dissolution Itis generally believed that the wider the diameter of thesemicircle the higher the corrosion resistance of the alloyThewider diameter obtained for the Fe-45Ni alloy confirmsthat this alloy has higher corrosion resistance than that for Fe-36 Ni alloy

For further studying the effect of the acid solution on theiron-nickel alloys the obtained EIS data were best simulatedto an equivalent circuit model and the schematic diagram forthat circuit is displayed in Figure 7 The elements depictedin Figure 7 can be defined as follows 119877119878 refers to theresistance of the solution 1198761 (1198841198761 CPEs) represents thefirst constant phase elements at the interface between thenickel alloy and solution R1199011 is the polarization resistanceat the electrodesolution interface1198762 (1198841198762 CPEs) representsanother constant phase elements at the interface between acorrosion product layer formed on the alloyrsquos surface and thesolution and 1198771199012 is the polarization resistance between thecorrosion product layer formed on the alloy and the solutioninterface and can also be defined as the charge transferresistance

The values for the elements of the equivalent circuit that ispresented in Figure 7 are listed in Table 2 The data shown inFigure 6 and the parameters listed in Table 2 confirm that thecorrosion resistance of Fe-45 Ni alloy is too high comparedto that obtained for Fe-36Ni alloyThis is because the valuesof 119877119878 1198771199011 and 1198771199012 for Fe-45 Ni alloy are much higherIt is worth mentioning also that the values of the CPEs (1198761and 1198762) with their 1198991 and 1198992 components were close to unity(exactly ranged from 081 to 10) and are considered as doublelayer capacitors [29ndash31]Thus obtained values of1198841198761 and1198841198762in the case of Fe-45 Ni alloy are smaller than the valuesrecorded for the Fe-36 Ni alloy


(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)

Figure 8 Typical Bode (a) impedance of the interface |119885| and (b) phase angle plots obtained for iron-nickel alloy (1) Fe-36 Ni and (2)Fe-45 Ni immersed in 1M HCl solutions

In order to throw more light on the dissolution of thetwo nickel alloys and to further understand the role ofincreasing Ni content in this process the Bode impedanceof the interface |119885| and Bode degree of phase angle (B)plots obtained for (1) Fe-36 Ni alloy and (2) Fe-45 Nialloy immersed in HCl solutions for 2400 s are shown inFigures 8(a) and 8(b) respectively It is seen from Figure 8(a)that the value of |119885| increases from the higher frequencyregion towards the low frequency region for the two nickelalloys but with higher |119885| values obtained for Fe-45Ni alloy(curve (2)) particularly at the low frequency area comparedto Fe-36 Ni alloy Furthermore Figure 8(b) depicts that themaximumvalues recorded forBwere obtained for Fe-45Nialloy (curve (2)) It is generally believed that the high values of|119885| at the low frequency regions as well as the increase of themaximum values of B indicate the high corrosion resistanceof the material and thus the corrosion resistance for Fe-45 Ni alloy is higher than Fe-36 Ni alloy The impedancedata thus prove that the increase of Ni content increases thecorrosion resistance of the iron-nickel alloys The EIS resultsthus agree with the data obtained by polarization OCP andchronoamperometric current-time measurements that Fe-45Ni alloy resists corrosion in 1MHCl solutionsmore thanFe-36 Ni alloy

4 Conclusions

The corrosion resistance of Fe-36 Ni alloy and Fe-45 Nialloy in 1M HCl solutions was investigated using differentelectrochemical and spectroscopic techniques The param-eters extracted from polarization curves indicated that thevalues of 119895Corr and 119877Corr were low while the value of 119877119901was high for Fe-45 Ni alloy compared to those valuesobtained for Fe-36 Ni alloy A potential difference of circa018 V (AgAgCl) in the less negative direction was recordedfor Fe-45 Ni alloy as indicated by OCP measurement

SEMEDS investigations after 96 h in the acid test solutionshowed that the surface of Fe-45 Ni alloy developed athicker corrosion product layer EIS data revealed that thediameter of the semicircle of the Nyquist plots was widerand also the values of surface and polarization resistanceswere higher for Fe-45 Ni alloy than those recorded for Fe-36Ni alloyThe current-timemeasurements confirmed thatthe absolute current values obtained for Fe-36 Ni alloy at0150V (AgAgCl) were higher as compared to the valuesobtained for Fe-45Ni alloy Results togetherwere consistentwith each other confirming that Fe-45 Ni alloy showedmuch better corrosion resistance than Fe-36Ni alloy in 1MHCl solutions

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

The authors would like to extend their sincere appreciation tothe Deanship of Scientific Research at King Saud Universityfor its funding of this research through the Research GroupProject no RGP-160

References

[1] O Yamada I Nakai H Fujiwara and F Ono ldquoHigh-fieldsusceptibility and magnetization in Fe-Ni invar alloysrdquo Journalof Magnetism and Magnetic Materials vol 10 no 2-3 pp 155-156 1979

[2] O Yamada F Ono and I Nakai ldquoThe Arrott plots and theitinerant electron character for Fe-Ni invar alloysrdquo Physica B+Cvol 91 pp 298ndash301 1977

[3] E P Wohlfarth ldquoInvar behaviour in crystalline and amorphousalloysrdquo Journal ofMagnetism andMagneticMaterials vol 10 no2-3 pp 120ndash125 1979


[4] D Jiles Introduction to Magnetism and Magnetic MaterialsChapman amp Hall London UK 1994

[5] Z-K Liu Y Wang and S Shang ldquoThermal expansion anomalyregulated by entropyrdquo Scientific Reports vol 4 p 7043 2014

[6] C Woolger ldquoInvar nickel-iron alloy 100 years onrdquo MaterialsWorld vol 4 no 6 pp 332-333 1996

[7] S-H Kim H-J Sohn Y-C Joo et al ldquoEffect of saccharinaddition on the microstructure of electrodeposited Fe-36wtNi alloyrdquo Surface and Coatings Technology vol 199 no 1 pp43ndash48 2005

[8] L L Hamer ldquoInvar at 100 yearsrdquo Advanced Materials andProcesses vol 151 pp 31ndash34 1997

[9] Y Ihara H Ohgame K Sakiyama and K Hashimoto ldquoThecorrosion behaviour of nickel in hydrogen chloride gas and gasmixtures of hydrogen chloride and oxygen at high tempera-turesrdquo Corrosion Science vol 22 no 10 pp 901ndash912 1982

[10] L Jinlong L Tongxiang and W Chen ldquoComparison of corro-sion behavior between coarse grained and nanocrystalline Ni-Fe alloys in chloride solutions and proton exchange membranefuel cell environment by EIS XPS and Raman spectra tech-niquesrdquo Energy vol 112 pp 67ndash74 2016

[11] H Konishi M Yamashita H Uchida and J Mizuki ldquoCharac-terization of rust layer formed on Fe Fe-Ni and Fe-Cr alloysexposed to Cl-rich environment by Cl and Fe K-Edge XANESmeasurementsrdquo Materials Transactions vol 46 no 2 pp 329ndash336 2005

[12] B Gehrmann H Hattendorf A Kolb-Telieps W Kramer andW Mottgen ldquoCorrosion behaviour of softmagnetic iron-nickelalloysrdquoMaterials and Corrosion vol 48 no 8 pp 535ndash541 1997

[13] D O Condit ldquoPotentiodynamic polarization studies of Fe-Ni binary alloys in sulfuric acid solution at 25∘Crdquo CorrosionScience vol 12 no 5 pp 451ndash462 1972

[14] E-S M Sherif J A Mohammed H S Abdo and A AAlmajid ldquoCorrosion behavior in highly concentrated sodiumchloride solutions of nanocrystalline aluminum processed byhigh energy ball millrdquo International Journal of ElectrochemicalScience vol 11 no 2 pp 1355ndash1369 2016

[15] E-SM Sherif H S Abdo J AMohammed A A Almajid andAH Seikh ldquoCorrosion of newlymanufactured nanocrystallineAl and two of its alloys in stagnant 40 NaCl solutionsrdquoInternational Journal of Electrochemical Science vol 11 no 6 pp4598ndash4610 2016

[16] E-S M Sherif H S Abdo K A Khalil and A M NabawyldquoEffect of titanium carbide content on the corrosion behaviorof Al-TiC composites processed by high energy ball millrdquoInternational Journal of Electrochemical Science vol 11 no 6 pp4632ndash4644 2016

[17] A AlOtaibi E-SM Sherif S Zinelis andY S Al Jabbari ldquoCor-rosion behavior of two cp titanium dental implants connectedby cobalt chromium metal superstructure in artificial salivaand the influence of immersion timerdquo International Journal ofElectrochemical Science vol 11 no 7 pp 5877ndash5890 2016

[18] M A Amin H H Hassan and S S Abd El Rehim ldquoOn therole of NO2

minus ions in passivity breakdown of Zn in deaeratedneutral sodiumnitrite solutions and the effect of some inorganicinhibitors Potentiodynamic polarization cyclic voltammetrySEM and EDX studiesrdquo Electrochimica Acta vol 53 no 5 pp2600ndash2609 2008

[19] A ShahryariW Kamal and S Omanovic ldquoThe effect of surfaceroughness on the efficiency of the cyclic potentiodynamicpassivation (CPP) method in the improvement of general and

pitting corrosion resistance of 316LVM stainless steelrdquoMaterialsLetters vol 62 no 23 pp 3906ndash3909 2008

[20] Z Bou-Saleh A Shahryari and S Omanovic ldquoEnhancementof corrosion resistance of a biomedical grade 316LVM stainlesssteel by potentiodynamic cyclic polarizationrdquo Thin Solid Filmsvol 515 no 11 pp 4727ndash4737 2007

[21] E-S M Sherif and A A Almajid ldquoAnodic dissolution ofAPI X70 pipeline steel in Arabian Gulf seawater after differentexposure intervalsrdquo Journal of Chemistry vol 2014 Article ID753041 7 pages 2014

[22] M Saremi and E Mahallati ldquoA study on chloride-induceddepassivation of mild steel in simulated concrete pore solutionrdquoCement and Concrete Research vol 32 no 12 pp 1915ndash19212002

[23] H Liu Y X Leng G Wan and N Huang ldquoCorrosion suscep-tibility investigation of Ti-O film modified cobalt-chromiumalloy (L-605) vascular stents by cyclic potentiodynamic polar-ization measurementrdquo Surface and Coatings Technology vol206 no 5 pp 893ndash896 2011

[24] V Shinde and P P Patil ldquoEvaluation of corrosion protectionperformance of poly(o-ethyl aniline) coated copper by elec-trochemical impedance spectroscopyrdquo Materials Science andEngineering B vol 168 no 1 pp 142ndash150 2010

[25] E-S M Sherif H S Abdo K A Khalil and A M NabawyldquoCorrosion properties in sodium chloride solutions of AlndashTiCcomposites in situ synthesized by HFIHFrdquoMetals vol 5 no 4pp 1799ndash1811 2015

[26] E-SM Sherif RM Erasmus and JD Comins ldquoIn situ Ramanspectroscopy and electrochemical techniques for studying cor-rosion and corrosion inhibition of iron in sodium chloridesolutionsrdquo Electrochimica Acta vol 55 no 11 pp 3657ndash36632010

[27] E-S M Sherif A T Abbas D Gopi and A M El-ShamyldquoCorrosion and corrosion inhibition of high strength low alloysteel in 20M sulfuric acid solutions by 3-Amino-123-triazoleas a corrosion inhibitorrdquo Journal of Chemistry vol 2014 ArticleID 538794 8 pages 2014

[28] F H Latief E-S M Sherif A A Almajid and H JunaedildquoFabrication of exfoliated graphite nanoplatelets-reinforced alu-minum composites and evaluating their mechanical propertiesand corrosion behaviorrdquo Journal of Analytical and AppliedPyrolysis vol 92 no 2 pp 485ndash492 2011

[29] A-C Ciubotariu L Benea M Lakatos-Varsanyi and V Dra-gan ldquoElectrochemical impedance spectroscopy and corrosionbehaviour of Al2O3-Ni nano composite coatingsrdquo Electrochim-ica Acta vol 53 no 13 pp 4557ndash4563 2008

[30] M Kendig and J Scully ldquoBasic aspects of electrochemicalimpedance application for the life prediction of organic coatingson metalsrdquo Corrosion vol 46 no 1 pp 22ndash29 1990

[31] F L Floyd S Avudaiappan J Gibson et al ldquoUsing electrochem-ical impedance spectroscopy to predict the corrosion resistanceof unexposed coated metal panelsrdquo Progress in Organic Coat-ings vol 66 no 1 pp 8ndash34 2009

[32] Y S Huang X T Zeng X F Hu and F M Liu ldquoCorrosionresistance properties of electroless nickel composite coatingsrdquoElectrochimica Acta vol 49 no 25 pp 4313ndash4319 2004

[33] C Cao ldquoOn electrochemical techniques for interface inhibitorresearchrdquoCorrosion Science vol 38 no 12 pp 2073ndash2082 1996

Submit your manuscripts athttpswwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



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NanoparticlesJournal of



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Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



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MaterialsJournal of



Table 1 Corrosion data obtained from the polarization curves for Fe-36 Ni and Fe-45 Ni in 1M HCl solutions

Alloy Corrosion parameter120573119888Vdecminus1 119864CorrV 120573119886Vdecminus1 119895Corr120583Acmminus2 119877119901Ωcm2 119877Corrmpy

Fe-36 Ni 0135 minus0475 0035 550 2197 1944Fe-45 Ni 0100 minus0248 0048 20 7050 0728

alloy improves its corrosion resistance [12] Another studyon the corrosion behavior of various iron-nickel alloys insulfuric acid solution using potentiodynamic polarizationtechnique has also been reported [13] For iron-nickel alloyscontaining up to 50 Ni a preferential dissolution of irontakes place and the percentage of iron controls the dissolutionprocess of the alloy It has been reported [14] that a toplayer of FeNi3 is formed for iron-nickel alloys that have morethan 40 iron in the alloy This was confirmed throughstudying the electrochemical corrosion behavior of differentFe-Ni alloys starting from 0 20 40 60 and 80 Niin sulfuric acid solution [14] Moreover the corrosion ratedecreases as the content of Ni increases in the alloy

This work aims at reporting the corrosion behavior of Fe-36 Ni and Fe-45 Ni alloys in concentrated hydrochloricacid (1M HCl) pickling solutions and understanding theeffect of increasing nickel content on the corrosion resistanceof the iron-nickel alloys For the best of our knowledgethe corrosion behavior of these alloys in hydrochloric acidsolutions has not been reported in the literature beforeThe study was carried out using various electrochemicaltechniques These methods included the use of potentiody-namic cyclic polarization open-circuit potential impedancespectroscopy and the change of the potentiostatic currentwith time at 0150V (AgAgCl) The corroded surfaces ofthe two nickel alloys after being immersed in 1M HClsolutions for 96 h were investigated using SEM and EDS Itwas expected that the alloy with high nickel content wouldshow better corrosion resistance due to the formation ofthicker oxides on the surface of the alloy protects it frombeing easily corroded

2 Materials and Methods

Two iron base alloys containing 36 Ni and 45 Ni with lessthan 1 of Mn + Si + C are named as Fe-36 Ni and Fe-45Ni alloys respectively These alloys have a cylindrical shapewith 60mm diameter and were purchased from Goodfellow(Ermine Business Park Huntingdon England PE29 6WR)Hydrochloric acid (HCl 32) was obtained fromMerck andwas used as received to prepare 1M concentration of theacid solution An electrochemical cell with three-electrodeconfiguration that accommodates for 300 cm3 was used toperform all electrochemical measurements The Fe-36 Niand Fe-45 Ni alloys were used as the working electrodesA silversliver chloride (AgAgCl) electrode was employed asthe reference electrode A Pt sheet was the counterelectrodein all electrochemical tests Only one surface of the iron-nickel electrodes were exposed to the electrolytic solutionwith 06 cm diameter and an area of 0283 cm2The surface ofthe iron-nickel alloys was polished and ground before being

immersed in the electrolytic solutions and performing theelectrochemical measurements as reported earlier [14ndash16]

All electrochemical measurements were performed usingan Autolab workstation (Metrohm Utrecht Netherlands)The CPP experiments were performed by scanning thepotential of the iron-nickel alloys in the hydrochloric acidtest solution from minus1200V in the positive direction to 080V(AgAgCl) at a scan rate of 0003Vs as has been reportedin our previous study [17] The EIS experiments were carriedout at the OCP after immersing the iron-nickel alloys aftertheir immersion in 1M HCl solutions for 2400 s The rangeof the frequency for the EIS was scanned from 100KHz to100mHz using an AC wave of plusmn5mV peak-to-peak overlaidon a DC bias potential The impedance data were collectedat a rate of 10 points per decade change in frequency usingPowersine software The change of the chronoamperometriccurrent for the iron-nickel electrodes versus time at 0150Vversus AgAgCl was applied for 3600 s after immersing thetested alloys in 1M HCl for 2400 s All electrochemical testswere carried out in triplicate and good reproducibility wasobserved All measurements were carried out on a fresh sur-face of the alloy with a new portion of the test solution SEMmicrographs and EDS profiles were obtained for the surfaceof the alloys after 96 hours of immersion in 1MHCl solutionsFor this purpose we used a scanning electron microscopewith an attached energy dispersive spectroscopy (JEOL)

3 Results and Discussion

31 CPP Measurements The cyclic potentiodynamic polar-ization (CPP) technique is a powerful method to obtainimportant information about the corrosion parameters ofmetals and alloys in corrosive media [18ndash23] Figure 1 showsthe CPP curves obtained for iron (1) Fe-36 Ni and (2)Fe-45 Ni immersed in 10M HCl solutions for 2400 sbefore measurements The values of cathodic Tafel (120573119888)slope corrosion potential (119864Corr) anodic Tafel (120573119886) slopecorrosion current density (119895Corr) polarization resistance (119877119901)and corrosion rate (119877Corr) that were obtained from the CPPcurves are depicted in Table 1 where the values of 119895Corr and119864Corr were obtained from the extrapolation of anodic andcathodic Tafel lines located next to the linearized currentregions [24ndash28] The values of 119877119901 were obtained from thepolarization curves using the following equation as reportedin the previous studies [24ndash28]

119877119901 = 1119895Corr (12057311988812057311988623 (120573119888 + 120573119886)) (1)



10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)

(a)

10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)


(b)



119877Corr = 119895Corr (119896119864119882119889119860 ) (2)



2H+ + 2eminus = H2 (3)





Fe + 12O2 +H2O = Fe (OH)2 (5)

3Fe (OH)2 + 12O2 = Fe3O4 + 3H2O (6)




(1)

(2)

5 10 15 20 25 30 35 400t (min)

minus045

minus040

minus035

minus030

minus025

minus020

E (V

) (A

gA

gCl)









(a)

Fe

Fe

FeNi

Ni

Ni

O

C

0 2 4 6 8

(b)


(a)

0 2 4 6 8

(b)


(2)

(1)

60

70

80

90

100

j(m

Acm

minus2)

300 600 900 1200 1500 18000t (s)






AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)




RP1

RP2

RS

Cdl

Q






(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of




10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)

(a)

10minus7

10minus6

10minus5

10minus4

10minus3

10minus2

10minus1

100

j(A

cmminus2)


(b)



119877Corr = 119895Corr (119896119864119882119889119860 ) (2)



2H+ + 2eminus = H2 (3)





Fe + 12O2 +H2O = Fe (OH)2 (5)

3Fe (OH)2 + 12O2 = Fe3O4 + 3H2O (6)




(1)

(2)

5 10 15 20 25 30 35 400t (min)

minus045

minus040

minus035

minus030

minus025

minus020

E (V

) (A

gA

gCl)









(a)

Fe

Fe

FeNi

Ni

Ni

O

C

0 2 4 6 8

(b)


(a)

0 2 4 6 8

(b)


(2)

(1)

60

70

80

90

100

j(m

Acm

minus2)

300 600 900 1200 1500 18000t (s)






AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)




RP1

RP2

RS

Cdl

Q






(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



(1)

(2)

5 10 15 20 25 30 35 400t (min)

minus045

minus040

minus035

minus030

minus025

minus020

E (V

) (A

gA

gCl)









(a)

Fe

Fe

FeNi

Ni

Ni

O

C

0 2 4 6 8

(b)


(a)

0 2 4 6 8

(b)


(2)

(1)

60

70

80

90

100

j(m

Acm

minus2)

300 600 900 1200 1500 18000t (s)






AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)




RP1

RP2

RS

Cdl

Q






(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



(a)

Fe

Fe

FeNi

Ni

Ni

O

C

0 2 4 6 8

(b)


(a)

0 2 4 6 8

(b)


(2)

(1)

60

70

80

90

100

j(m

Acm

minus2)

300 600 900 1200 1500 18000t (s)






AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)




RP1

RP2

RS

Cdl

Q






(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of




AlloyEIS parameter

119877119878Ω 1198761 1198771198751Ω 1198762 1198771198752Ω1198841198761F 1198991 1198841198761F 1198992Fe-36 Ni 271 006414 088 766 0002859 081 1166Fe-45 Ni 354 002633 10 2709 0002612 094 1385

(1)

(2)59 Hz

24 Hz 0197 Hz 077 Hz

24 Hz47 Hz

93 Hz

288 Hz

300 600 900 1200 15000Z998400998400 (Ωcm2)

0

300

600

900

1200

1500

minusZ

998400(Ω

cm2)




RP1

RP2

RS

Cdl

Q






(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of



(2)

(1)

100

101

102

103

104|Z

|(Ω

cm2)

100 101 102 103 104 10510minus1

Frequency (Hz)

(a)

(2)

(1)

minus20

0

20

40

60

80

Phas

e ang

(de

g)

100 101 102 103 104 10510minus1

Frequency (Hz)

(b)



4 Conclusions





Acknowledgments


References












































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of










































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


effect of nickel content on the corrosion resistance of iron...

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