Recent work has indicated that a galvanic as well as chemical protection mechanism may control the intergranular stress corrosioncracking (IG-SCC) mitigation achieved by Zn-rich primers on Al-Mg alloys [1]. The effect of Zn salt species content added to the bulk NaCl environment on IG-SCC severity at -0.9 VSCE was evaluated using a highly susceptible condition of AA5456-H116. Linear elastic fracture mechanics-based testing demonstrated that, for a constant [Cl–], the threshold stress intensity for IG-SCC increased under these conditions and the IG-SCC growth rate was significantly suppressed with increasing stress intensity in the presence of Zn ions. Titration of ZnCl2 into Al-Mg simulated crack tip solution indicates that Zn salt species may reduce crack tip acidification and thereby raise the pH of the crack tip. These results support the combined galvanic and chemical protection that may be achieved through use of Zn-rich primers for IG-SCC mitigation on AA5456-H116.
McMahonMEScullyJrBurnsJT.Mitigation of intergranular cracking in Al-Mg Alloys via Zn-based electrode potential control in sodium chloride solution. Corrosion. 2019. doi:10.5006/3185.
2.
NiederbergerRBBasilJLBedfordGT.Corrosion and stress corrosion of 5000-series Al Alloys in marine environments. Corrosion. 1966; 22: 68–73. doi:10.5006/0010-9312-22.3.68.
3.
HolroydNJHScamansGM.Environmental degradation of marine aluminum alloys—past, present, and future. Corrosion. 2016; 72: 136–143. doi:10.5006/1927.
4.
DixEHAndersonWAShumakerMB.Influence of service temperature on the resistance of wrought aluminum-magnesium alloys to corrosion. Corrosion. 1959; 15: 55–62. doi: 10.5006/0010-9312-15.2.19
5.
DavenportAJYuanYAmbatR. Intergranular corrosion and stress corrosion cracking of sensitised AA5182. Mater Sci Forum. 2006; 519-521: 641–646. doi:10.4028/www.scientific.net/MSF.519-521.641.
6.
JonesRH.The influence of hydrogen on the stress-corrosion cracking of Low-strength Al-Mg alloys. J. Miner. Met. Mater. 2003; 55: 42–46. doi:10.1007/s11837-003-0225-5.
7.
SeifiMHolroydNJHLewandowskiJJ.Deformation rate and sensitization effects on environmentally assisted cracking of Al-Mg naval alloys. Corrosion. 2016; 72: 264–283. doi:10.5006/1949.
8.
ScullyJrYoungGASmithS.Hydrogen embrittlement of aluminum and aluminum-based alloys. In: GangloffRPSomerdayBP, editors. Gaseous hydrogogen embrittlement of materials in energy technologies. 1st ed.Cambridge: Woodhead Publishing Limited; 2012. p. 707–768.
9.
RajaVSShojiT.Stress corrosion cracking: Theory and practice. Cambridge: Woodhead Publishing Limited; 2011.
10.
LimMLCKellyRGScullyJR.Overview of intergranular corrosion mechanisms, phenomenological observations, and modeling of AA5083. Corrosion. 2016; 72: 198–220. doi:10.5006/1818.
11.
HolroydNJHScamansGM.The role of magnesium during environment-sensitive fracture of aluminium alloys. Scr Metall Mater. 1985; 19: 945–946.
12.
BaerDrWindshCF.JREngelhardMH. Influence of Mg on the corrosion of Al. J Vac Sci Technol. A. 2000; 18: 131–136. doi:10.1116/1.582129.
13.
JonesRHVetranoJSWindischCF.Stress corrosion cracking of Al-Mg and Mg-Al alloys. Corrosion. 2004; 60: 1144–1154. doi:10.5006/1.3299228.
14.
VetranoJSWillifordREBruemmerSM. Influence of microstructure and thermal history on the corrosion susceptibility of AA 5083. In: Automotive alloys; 1997.
JonesRHBaerDrDanielsonMJ. Role of Mg in the stress corrosion cracking of an Al-Mg alloy. Metall Mater Trans A. 2001; 32: 1699–1711. doi:10.1007/s11661-001-0148-0.
17.
McMahonMESteinerPJLassAB. The effect of temper and composition on the stress corrosion cracking of Al-Mg alloys. Corrosion. 2017; 73: 347–361. doi:10.5006/2317.
18.
BirbilisNZhangRLimMLC. Quantification of sensitization in AA5083-H131 via Imaging Ga-Embrittled fracture surfaces. Corrosion. 2013; 69: 396–402. doi:10.5006/0804.
19.
LimMLCScullyJrKellyRG.Intergranular corrosion Penetration in an Al-Mg Alloy as a Function of electrochemical and Metallurgical conditions. Corrosion. 2013; 69: 35–47. doi:10.5006/0722.
20.
LimMLCScullyJrKellyRG.Critical electrochemical conditions for intergranular corrosion in sensitized AA5083-H131. In: Department of Defense Virtual Corrosion Conference; 2013.
21.
JainSLimMLCHudsonJL. Spreading of intergranular corrosion on the surface of sensitized Al-4.4Mg alloys: a general finding. Corros Sci. 2012; 59: 136–147. doi:10.1016/j.corsci.2012.02.018.
22.
SteinerMAAgnewSR.Modeling sensitization of Al–Mg alloys via β-phase precipitation kinetics. Scr Mater. 2015; 102: 55–58. doi:10.1016/j.scriptamat.2015.02.012.
23.
GolumbfskieWJTranKTNolandJM. Survey of detection, mitigation, and repair technologies to address problems caused by sensitization of Al-Mg alloys on navy ships. Corrosion. 2016; 72: 314–328. doi:10.5006/1916.
24.
CraneCBKellyRGangloffRP.Crack chemistry control of intergranular stress corrosion cracking in sensitized Al-Mg. Corrosion. 2016; 72: 242–263. doi:10.5006/1852.
25.
CraneCBGangloffRP.Stress corrosion cracking of Al-Mg alloy 5083 sensitized at low temperature. Corrosion. 2016; 72: 221–241. doi:10.5006/1766.
26.
McMahonMESteinerPJLassAB. The effect of loading orientation on intergranular stress corrosion cracking in Al-Mg alloys. Corrosion. 2017; 73: 713–723. doi:10.5006/2343.
27.
McMahonMEScullyJrBurnsJT.Mitigation of intergranular stress corrosion cracking in Al-Mg by electrochemical potential control. J Miner Met Mater. 2017; 69: 1389–1397. doi:10.1007/s11837-017-2362-2.
28.
SteinerPBurnsJ.Mechanistic studies of intergranular stress corrosion cracking in Al-Mg Alloys under atmospheric exposure conditions. Corrosion. 2018; 74: 1117–1131. doi:10.5006/2853.
29.
NatishanPMGradyWEOMccaffertyE. Chloride uptake by oxide covered aluminum as determined by X-Ray Photoelectron and X-Ray absorption spectroscopy. J Electrochem Soc. 1999; 146: 1737–1740. doi:10.1149/1.1391835.
30.
McCaffertyE.Sequence of steps in the pitting of aluminum by chloride ions. Corros Sci. 2003; 45: 1421–1438. doi:10.1016/S0010-938X(02)00231-7.
31.
FoleyRT.Localized corrosion of aluminum alloys – a review. Corrosion. 1986; 42: 277–288. doi:10.5006/1.3584905.
32.
AiJ-HLimMLCScullyJR.Effective hydrogen diffusion in aluminum alloy 5083-H131 as a function of orientation and degree of sensitization. Corrosion. 2013; 69: 1225–1239. doi:10.5006/0987.
33.
LimMLCMatthewsROjaM. Model to predict intergranular corrosion propagation in three dimensions in AA5083-H131. Mater Des. 2016; 96: 131–142. doi: 10.1016/j.matdes.2016.01.089
34.
SakairiMOtaniKSasakiR.Electrochemical noise evaluation of metal cation effects on galvanic corrosion of aluminum alloys in low concentration of chloride ion containing solutions. Procedia Eng. 2014; 86: 589–596. doi:10.1016/j.proeng.2014.11.084.
35.
KhedrMGALashienAMS.The role of metal cations in the corrosion and corrosion inhibition of aluminum in aqueous solutions. Corros. Sci. 1992; 33: 137–151. doi: 10.1016/0010-938X(92)90023-V
36.
KhedrMLashienA.Corrosion behavior of aluminum in the presence of accelerating metal cations and inhibition. J Electrochem Soc. 1989; 136: 968–972. doi:10.1149/1.2096895.
37.
BuchheitRGGuanHMahajanamS. Active corrosion protection and corrosion sensing in chromate-free organic coatings. Prog Org Coatings. 2003; 47: 174–182. doi:10.1016/j.porgcoat.2003.08.003.
38.
MahajanamSBuchheitRG.Characterization of inhibitor release from Zn-Al- [V10 O28]6- Hydrotalcite pigments and corrosion protection from hydrotalcite-pigmented Epoxy coatings. Corrosion. 2008; 64: 230–240. doi: 10.5006/1.3278468
39.
LiuCYangVAKellyRG.Inhibition of cathodic kinetics by Zn 2+ and Mg 2+ on AA7050-T7451. J Electrochem Soc. 2019; 166: C134–C146. doi:10.1149/2.0551906jes.
40.
IslamS.Effects of Zn 2 + concentration on the corrosion of Mild steel in NaCl aqueous solutions. J Electrochem Soc. 2019; 166: 83–90. doi:10.1149/2.1271902jes.
41.
TadaESatohSKanekoH.The spatial distribution of Zn2+during galvanic corrosion of a Zn/steel couple. Electrochim Acta. 2004; 49: 2279–2285. doi:10.1016/j.electacta.2004.01.008.
42.
VolovitchPAllelyCOgleK.Understanding corrosion via corrosion product characterization: I. case study of the role of Mg alloying in Zn-Mg coating on steel. Corros Sci. 2009; 51: 1251–1262. doi:10.1016/j.corsci.2009.03.005.
43.
VolovitchPVuTNAllélyC. Understanding corrosion via corrosion product characterization: II. role of alloying elements in improving the corrosion resistance of Zn-Al-Mg coatings on steel. Corros Sci. 2011; 53: 2437–2445. doi:10.1016/j.corsci.2011.03.016.
DrazicDMVorkapicLZ.Inhibitory effects of manganeous, cadmium, and zinc ions on hydrogen evolution reaction and corrosion of iron in sulphuric acid solutions. Corros Sci. 1978; 18: 907–910. doi: 10.1016/0010-938X(78)90011-2
46.
ZhangSShibataTHarunaT.Inhibition effect of metal cations to intergranular stress corrosion cracking of sensitized type 304 stainless steel. Corros Sci. 2005; 47: 1049–1061. doi:10.1016/j.corsci.2004.06.014.
47.
NiedrachLWStoddardWH.Technical Note: effect of zinc on corrosion films that form on stainless steel. Corrosion. 2011; 42: 546–549. doi:10.5006/1.3583066.
48.
AngeliuTMAndresenPL.Effect of zinc additions on oxide rupture strain and repassivation kinetics of iron-based alloys in 288°C water. Corrosion. 1996; 52: 28–35. doi:10.5006/1.3292092.
49.
GangloffRPSlavikDCPiascikS. Direct current electrical potential measurement of the growth of small cracks. In: LarsenJMAllisonJE, editors. Small-crack test methods, American Society for Testing and Materials. Philadelphia (PA): American Society for Testing and Materials; 1992. p. 116–168.
50.
PopernackA.Loading rate effects on the hydrogen enhanced cracking behavior of Ni- and Co-based superalloys for marine applications. Charlottesville (VA): University of Virginia; 2017.
51.
GangloffRHaHBurnsJ. Measurement and modeling of hydrogen environment-assisted cracking in Monel K-500. Metall Mater Trans A. 2014; 45: 3814–3834. doi: 10.1007/s11661-014-2324-z
52.
BumillerE.Intergranular corrosion in AA5xxx aluminum alloys with discontinuous precipitation at the grain boundaries. Charlottesville (VA): Univesity of Virginia; 2011.
53.
LimMLC.Intergranular corrosion propagation in sensitized Al-Mg alloys. Charlottesville (VA): The University of Virginia; 2016.
54.
McMahonMEHarrisZDScullyJr. The effect of electrode potential on stress corrosion cracking in highly sensitized Al-Mg alloys. Mater Sci Eng A. 2019; 767: 1–19. doi: 10.1016/j.msea.2019.138399
55.
McMahonMESantucciRJJRScullyJR.Advanced chemical stability diagrams to predict the formation of complex zinc compounds in chloride environment. RSC Adv. 2019; 9: 19905–19916. doi:10.1039/c9ra00228f.
56.
Szklarska-SmialowskaZ.Pitting corrosion of aluminum. Corros Sci. 1999; 41: 1743–1767. doi:10.1016/S0010-938X(99)00012-8.
57.
Szklarska-SmialowskaZ.Pitting and crevice corrosion. Houston (TX): NACE International; 2005.
58.
RodilEVeraJH.Individual activity coefficients of chloride ions in aqueous solutions of MgCl2, CaCl2 and BaCl2 at 298.2 K. Fluid Phase Equilib. 2001; 188: 15–27. doi: 10.1016/S0378-3812(01)00523-4
59.
BrownBF.Stress corrosion cracking in high strength alloys. In: ScullyJC, editor. Theory of stress corrosion in alloys. Brussels: NATO Scientific Affairs Division; 1971. p. 186.
60.
BuckleyPPlaczankisBBeattyJ. Characterization of the hydrogen embrittlement behavior of high-strength steels for army applications. In: Corrosion 94, NACE International, Houston, TX; 1994, Paper No. 57.
61.
HarrisZDDolphJDPioszakGL. The effect of microstructural variation on the hydrogen environment-assisted cracking of Monel K-500. Metall Mater Trans A Phys Metall Mater Sci. 2016: 1–23. doi:10.1007/s11661-016-3486-7.
62.
TotsukaNSzklarska-SmialowskaZ.Effect of electrode potential on the hydrogen-induced IGSCC of alloy 600 in an aqueous solution at 350 C. Corrosion. 1987; 43: 734–738. doi:10.5006/1.3583860.
63.
BurnellGHardieDParkinsRN.Stress corrosion and hydrogen embrittlement of two precipitation hardening stainless steels. Br Corros. J. 1987; 22: 229–237. doi: 10.1179/000705987798271253
64.
DasKBSmithWGFingerRW. Hydrogen embrittlement of cathodically protected 15-5 PH stainless steel. In: Proceedings of the 2nd International Congress on Hydrogen in Metals. Oxford: Pergamon; 1977.
65.
TylerPSLevyMRaymondL.Investigation of the conditions for crack propagation and arrest under cathodic polarization by rising step load bend testing. Corrosion. 1991; 47: 82–87. doi:10.5006/1.3585857.
66.
KehlerBAScullyJR.Predicting the effect of applied potential on crack Tip hydrogen in Low-alloy martensitic steels. Corrosion. 2007; 64: 465–477. doi:10.5006/1.3278484.
67.
HarttWHKumriaCCKesslerRJ.Influence of potential, chlorides, pH, and precharging time on embrittlement of cathodically polarized prestressing steel. Corrosion. 1993; 49: 377–385. doi:10.5006/1.3316064.
68.
NishimuraR.The effect of potential on stress corrosion cracking of type 316 and type 310 austenitic stainless steels. Corros Sci. 1993; 34: 1463–1473. doi:10.1016/0010-938X(93)90241-8.
69.
YoungLMYoungGAScullyJr. Aqueous environmental crack propagation in high-strength beta titanium alloys. Metall Mater Trans A. 1995; 26: 1257–1271. doi:10.1007/BF02670620.
70.
KolmanDGScullyJR.Understanding the potential and pH dependency of high-strength β-titanium alloy environmental crack initiation. Metall Mater Trans A Phys Metall Mater Sci. 1997; 28: 2645–2656. doi:10.1007/s11661-997-0021-x.
