Skip to main content Accessibility help

An Examination of the Composition and Microstructure of Coarse Intermetallic Particles in AA2099-T8, Including Li Detection

  • Colin M. MacRae (a1), Anthony E. Hughes (a1) (a2) (a3), James S. Laird (a1), A. M. Glenn (a1), Nicholas C. Wilson (a1), Aaron Torpy (a1), Mark A. Gibson (a3) (a4), Xiaorong Zhou (a5), Nick Birbilis (a3) and George E. Thompson (a5)...


Electron and proton microprobes, along with electron backscatter diffraction (EBSD) analysis were used to study the microstructure of the contemporary Al–Cu–Li alloy AA2099-T8. In electron probe microanalysis, wavelength and energy dispersive X-ray spectrometry were used in parallel with soft X-ray emission spectroscopy (SXES) to characterize the microstructure of AA2099-T8. The electron microprobe was able to identify five unique compositions for constituent intermetallic (IM) particles containing combinations of Al, Cu, Fe, Mn, and Zn. A sixth IM type was found to be rich in Ti and B (suggesting TiB2), and a seventh IM type contained Si. EBSD patterns for the five constituent IM particles containing Al, Cu, Fe, Mn, and Zn indicated that they were isomorphous with four phases in the 2xxx series aluminium alloys including Al6(Fe, Mn), Al13(Fe, Mn)4 (two slightly different compositions), Al37Cu2Fe12 and Al7Cu2Fe. SXES revealed that Li was present in some constituent IM particles. Al SXES mapping revealed an Al-enriched (i.e., Cu, Li-depleted) zone in the grain boundary network. From the EBSD analysis, the kernel average misorientation map showed higher levels of localized misorientation in this region, suggesting greater deformation or stored energy. Proton-induced X-ray emission revealed banding of the TiB2 IM particles and Cu inter-band enrichment.


Corresponding author

Author for correspondence: Colin M. MacRae, E-mail:


Hide All
Ambat, R Dwarakadasa, ES (1992) The influence of pH on the corrosion of medium strength aerospace alloys 8090, 2091 and 2014. Corr Sci 33(5), 681690.
Boag, A, Taylor, RJ, Muster, TH, Goodman, N, McCulloch, D, Ryan, C, Rout, B, Jamieson, D Hughes, AE (2010) Stable pit formation on AA2024-T3 in a NaCl environment. Corr Sci 52(1), 90103.
Boag, AP, McCulloch, DG, Jamieson, DN, Hearne, SM, Hughes, AE, Ryan, CG Toh, SK (2005) Combined nuclear microprobe and TEM study of corrosion pit nucleation by intermetallics in aerospace aluminium alloys. Nucl Instrum Methods Phys Res Sec B 231, 457462.
Brodusch, N, Voisard, F Gauvin, R (2017) About the contrast of δ’ precipitates in bulk Al–Cu–Li alloys in reflection mode with a field‐emission scanning electron microscope at low accelerating voltage. J Microsc 268(2), 107118.
Bruhwiler, PA, Wagner, JL, Biggs, BD, Shen, Y, Wong, KM, Schnatterly, SE Poon, SJ (1988) Soft-x-ray, heat-capacity, and transport measurements on icosahedral and crystalline alloys. Phys Rev B Condens Matter 37(11), 65296532.
Buchheit, RG (2000) The electrochemistry of theta (Al2Cu), S (Al2CuMg) and T-1 (Al2CuLi) and localized corrosion and environment assisted cracking in high strength Al alloys. In Aluminium Alloys: Their Physical and Mechanical Properties, Pts. 1–3; vol. 331–333, Starke EA, Sanders TH and Cassada WA (Eds.), pp. 16411646. Cham, Switzerland: Wiley-VCH.
Buchheit, RG, Moran, JP Stoner, GE (1990) Localized corrosion behavior of alloy-2090 – the role of microstructural heterogeneity. Corrosion 46(8), 610617.
Buchheit, RG, Moran, JP Stoner, GE (1994) Electrochemical-behavior of the T-1 (Al2CuLi) intermetallic compound and its role in localized corrosion of Al-2-percent-Li-3-percent-Cu alloys. Corrosion 50(2), 120130.
Carrick, DM, Hogg, SC Wilcox, GD (2013) Corrosion of an advanced Al-Cu-Li alloy for aerospace applications. Mater Sci Forum 765, 629633.
Carrick, DM, Hogg, SC Wilcox, GD (2014) Investigation into the impact of lithium additions on the corrosion response of Al-Cu alloys for aerospace applications. Corr Manage 122, 1418.
Chen, A, Zhang, L, Wu, G, Peng, Y Li, Y (2016) Effect of Mn addition on microstructure and mechanical properties of cast Al-2Li-2Cu-0.8Mg-0.4Zn-0.2Zr alloy. J Mater Res 31(2), 250258.
Davo, B, Conde, A de Damborenea, JJ (2005) Inhibition of stress corrosion cracking of alloy AA8090 T-8171 by addition of rare earth salts. Corr Sci 47(5), 12271237.
Davo, B de Damborenea, JJ (2004) Use of rare earth salts as electrochemical corrosion inhibitors for an Al-Li-Cu (8090) alloy in 3.56% NaCl. Electrochim Acta 49(27), 49574965.
Dorin, T, Deschamps, A, Geuser, FD Sigli, C (2014) Quantification and modelling of the microstructure/strength relationship by tailoring the morphological parameters of the T1 phase in an Al-Cu-Li alloy. Acta Mater 75, 134146.
Drouin, D, Couture, AR, Joly, D, Tastet, X, Aimez, V Gauvin, R (2007) CASINO V2.42 - A fast and easy-to-use modeling tool for scanning electron microscopy and microanalysis users. Scanning 29(3), 92101.
Dursun, T Soutis, C (2014) Recent developments in advanced aircraft aluminium alloys. Mater Design 56, 862871.
Feng, Z, Yang, Y, Huang, B, Luo, X, Li, M, Chen, Y, Han, M, Fu, M Ru, J (2013) HRTEM and HAADF-STEM tomography investigation of the heterogeneously formed S (Al2CuMg) precipitates in Al–Cu–Mg alloy. Philos Mag 93(15), 18431858.
Garrard, WN (1994) Corrosion behavior of aluminum-lithium alloys. Corrosion 50(3), 215225.
Goodings, DA (1965) Interpretation of the soft X-ray emission spectrum of lithium metal. Proc Phys Soc 86(1), 7585.
Grilli, R, Baker, MA, Castle, JE, Dunn, B Watts, JF (2010) Localized corrosion of a 2219 aluminium alloy exposed to a 3.5% NaCl solution. Corr Sci 52(9), 28552866.
Grushko, B, Pavlyuchkov, D, Mi, SB Balanetskyy, S (2016) Ternary phases forming adjacent to Al3Mn-Al4Mn in Al-Mn-TM (TM = Fe, Co, Ni, Cu, Zn, Pd). J Alloys Compd 677, 148162.
Guérin, M, Alexis, J, Andrieu, E, Laffont, L, Lefebvre, W, Odemer, G Blanc, C (2016) Identification of the metallurgical parameters explaining the corrosion susceptibility in a 2050 aluminium alloy. Corr Sci 102, 291300.
Guérin, M, Andrieu, E, Odemer, G, Alexis, J Blanc, C (2014) Effect of varying conditions of exposure to an aggressive medium on the corrosion behavior of the 2050 Al-Cu-Li alloy. Corr Sci 85, 455470.
Hatch, JE (1984) Aluminium: Properties and Physical Metallurgy. Metals Park, OH: ASM International.
Holroyd, NJH, Scamans, GM, Newman, RC Vasudevan, AK (2014) Corrosion and stress corrosion of aluminum–lithium alloys. In Aluminum-Lithium Alloys: Processing, Properties and Applications, Prasad NE, Gokhale AA and Wanhill RJH (Eds.), pp. 457–500. Oxford: Butterworth-Heinemann, Elsevier.
Hovington, P, Timoshevskii, V, Burgess, S, Demers, H, Statham, P, Gauvin, R Zaghib, K (2016) Can we detect Li K X‐ray in lithium compounds using energy dispersive spectroscopy? Scanning 38(6), 571578.
Huang, W, Ma, Y, Zhou, X, Meng, X, Liao, Y, Chai, L, Yi, Y Zhang, X (2016) Correlation between localized plastic deformation and localized corrosion in AA2099 aluminum-lithium alloy. Surf Interface Anal 48(8), 838842.
Hughes, AE, Glenn, AM, Wilson, N, Moffatt, A, Morton, AJ Buchheit, RG (2013) A consistent description of intermetallic particle composition: An analysis of ten batches of AA2024-T3. Surf Interface Anal 45, 15581563.
Hughes, AE, MacRae, C, Wilson, N, Torpy, A, Muster, TH Glenn, AM (2010) Sheet AA2024-T3: a new investigation of microstructure and composition. Surf Interface Anal 42(4), 334338.
Ishida, N Fujita, D (2013) Chemical-state imaging of Li using scanning Auger electron microscopy. J Electron Spectrosc Relat Phenom 186(1), 3943.
Jamieson, DN, Rout, B, Szymanski, R, Spizzirri, P, Sakellariou, A, Belcher, W Ryan, CG (2002) The new Melbourne nuclear microprobe system. Nucl Instrum Methods Phys Res Sec B 190(1-4), 5459.
Jiang, N, Gao, X Zheng, ZQ (2010) Microstructure evolution of aluminum-lithium alloy 2195 undergoing commercial production. Trans Nonferrous Met Soc China (English Edition) 20(5), 740745.
Li, JF, Birbilis, N, Liu, DY, Chen, YL, Zhang, XH Cai, C (2016) Intergranular corrosion of Zn-free and Zn-microalloyed Al–xCu–yLi alloys. Corr Sci 105, 4457.
Liu, Y, Visser, P, Zhou, X, Lyon, SB, Hashimoto, T, Curioni, M, Gholinia, A, Thompson, GE, Smyth, G, Gibbon, SR, Graham, D, Mol, JMC Terrynb, H (2016) Protective film formation on AA2024-T3 Aluminum Alloy by leaching of lithium carbonate from an organic coating. J Electrochem Soc 163(3), C45C53.
Luo, C, Albu, SP, Zhou, X, Sun, Z, Zhang, X, Tang, Z Thompson, GE (2016 a) Continuous and discontinuous localized corrosion of a 2xxx aluminium-copper-lithium alloy in sodium chloride solution. J Alloys Compd 658, 6170.
Luo, C, Zhang, X, Zhou, X, Sun, Z, Tang, Z, Lu, F Thompson, GE (2016 b) Characterization of Localized Corrosion in an Al-Cu-Li Alloy. J Mater Eng Perform 25(5), 18111819.
Ma, Y, Zhou, X, Huang, W, Thompson, GE, Zhang, X, Luo, C Sun, Z (2015) Localized corrosion in AA2099-T83 aluminum-lithium alloy: The role of intermetallic particles. Mater Chem Phys 161, 201210.
Ma, Y, Zhou, X, Liao, Y, Yi, Y, Wu, H, Wang, Z Huang, W (2016) Localised corrosion in AA 2099-T83 aluminium-lithium alloy: The role of grain orientation. Corr Sci 107, 4148.
Ma, Y, Zhou, X, Thompson, GE, Hashimoto, T, Thomson, P Fowles, M (2011) Distribution of intermetallics in an AA 2099-T8 aluminium alloy extrusion. Materials Chemistry and Physics 126(1–2), 4653.
Mallinson, CF, Castle, JE Watts, JF (2013) Analysis of the Li KLL auger transition on freshly exposed lithium and lithium surface oxide by AES. Surf Sci Spectra 20(1), 113127.
Meletis, EI (1987) Microstructure and stress-corrosion cracking relationship in an AlLiCuZr alloy. Mater Sci Eng 93(C), 235245.
Mondolfo, LF (1976) Aluminum Alloys: Structure and Properties. London, UK: Butterworth & Co.
Neddermeyer, H Wiech, G (1970) Soft X-ray L-emission spectrum of aluminium. Phys Lett A 31(1), 1718.
Ott, N, Kairy, SK, Yan, Y Birbilis, N (2017) Evolution of grain boundary precipitates in an Al-Cu-Li alloy during aging. Metall Mater Trans A 48(1), 5156.
Ott, N, Yan, Y, Ramamurthy, S, Kairy, S Birbilis, N (2016) Auger electron spectroscopy analysis of grain boundary microchemistry in an Al-Cu-Li alloy. Scripta Mater 119, 1720.
Ovcharenko, RE, Tupitsyn, II, Kuznetsov, VG Shulakov, AS (2011) Study of mechanisms of formation of X-Ray emission bands in crystals by the density functional method: The Mg L 2,3 bands in metal and in MgO. Opt Spectrosc (English Translation of Optika i Spektroskopiya) 111(6), 940948.
Ovcharenko, RE, Tupitsyn, II, Savinov, EP, Voloshina, EN, Dedkov, YS Shulakov, AS (2014) Calculation of the X-Ray emission K and L 2,3 bands of metallic magnesium and aluminum with allowance for multielectron effects. J Exp Theor Phys 118(1), 1117.
Ovcharenko, RE, Tupitsyn, II, Savinov, EP, Voloshina, EN, Paulus, B, Dedkov, YS Shulakov, AS (2013) Specific many-electron effects in X-ray spectra of simple metals and graphene. Phys Chem Chem Phys 15(18), 67496756.
Parvizi, R, Hughes, AE, Tan, MY, Marceau, RKW, Forsyth, M, Cizek, P Glenn, AM (2017) Probing corrosion initiation at interfacial nanostructures of AA2024-T3. Corr Sci 116, 98109.
Phragmen, G (1950) On the phases occurring in alloys of aluminium with copper, magnesium, manganese, iron and silicon. J Inst Met 77, 489553.
Pownceby, MI, MacRae, CM Wilson, NC (2007) Mineral characterisation by EPMA mapping. Miner Eng 20(5), 444451.
Proton, V, Alexis, J, Andrieu, E, Delfosse, J, Deschamps, A, De Geuser, F, Lafont, MC Blanc, C (2014) The influence of artificial ageing on the corrosion behaviour of a 2050 aluminium-copper-lithium alloy. Corr Sci 80, 494502.
Rajput, SS, Singru, RM Prasad, R (1994) KKR-CPA calculations of density of states and soft X-ray emission from disordered Li-Mg alloys. Solid State Commun 90(5), 339342.
Rioja, RJ Liu, J (2012) The evolution of Al-Li base products for aerospace and space applications. Metall Mater Trans A 43(9), 33253337.
Ryan, CG, Cousens, DR, Sie, SH, Griffin, WL, Suter, GF Clayton, E (1990) Quantitative pixe microanalysis of geological matemal using the CSIRO proton microprobe. Nucl Instrum Methods Phys Res Sect B 47(1), 5571.
Schöberl, T Kumar, S (1997) Depletion of lithium due to surface oxidation: An investigation of an Al-Li-sheet by Auger-spectroscopy. J Alloys Compd 255(1–2), 135141.
Sha, G, Marceau, RKW, Gao, X, Muddle, BC Ringer, SP (2011) Nanostructure of aluminium alloy 2024: Segregation, clustering and precipitation processes. Acta Mater 59(4), 16591670.
Shek, ML, Hrbek, J, Sham, TK Xu, GQ (1990) A soft X-ray study of the interaction of oxygen with Li. Surf Sci 234(3), 324334.
Shek, ML, Sham, TK, Hrbek, J Xu, GQ (1991) A soft X-ray study of a LiS surface compound. Appl Surf Sci 48, 332336.
Shulakov, AS, Stepanov, AP, Brajko, AP, Müller, H, Kirchmayr, H Szasz, A (1993) Surface oxidation of dilute AlMgSi alloys. J Electron Spectrosc Relat Phenom 62(4), 351358.
Sperry, P (1956) The intermetallic particles in 2024 aluminum alloy. TransAm Soc Met 48, 904918.
Sukiman, NL, Zhou, X, Birbilis, N, Hughes, AE, Mol, JMC, Garcia, SJ, Zhou, X Thompson, GE (2012) Durability and corrosion of aluminium and its alloys: overview, property space, techniques and developments. In Aluminium Alloys – New Trends in Fabrication and Applications, Ahmad Z (Ed.), pp 47–97. Rijeka, Croatia: Intech Publications.
Szymanski, R, Jamieson, DN, Hughes, AE, Mol, A, van der Zwaag, S Ryan, CG (2002) Filiform corrosion imaged beneath protection layers on Al alloys. Nucl Instrum Methods Phys Res Sect B 190, 365369.
Takahashi, H, Murano, T, Takakura, M, Asahina, S, Terauchi, M, Koike, M, Imazono, T, Koeda, M Nagano, T (2016) Development of soft X-ray emission spectrometer for EPMA/SEM and its application. IOP Conf Ser Mater Sci Eng 109, 012017.
Tsuji, J, Kojima, K, Ikeda, S, Nakamatsu, H, Mukoyama, T Taniguchi, K (2001) Li K-edge spectra of lithium halides. J Synchrotron Radiat 8(2), 554556.
Visser, P, Terryn, H Mol, JMC (2016) Aerospace coatings. Springer Ser Mater Sci 233, 315372.
Warner, T (2006) Recently-developed aluminium solutions for aerospace applications. Mater Sci Forum 519-521, 12711278.
Wilson, N, MacRae, C Torpy, A (2008) Analysis of combined multi-signal hyperspectral datasets using a clustering algorithm and visualisation tools. Microsc Microanal 14(Suppl 2), 764765.
Wu, X Hebert, K (1996) Development of Surface Impurity Segregation during Dissolution of Aluminum. J Electrochem Soc 143(1), 8391.
Zhou, X, Luo, C, Ma, Y, Hashimoto, T, Thompson, GE, Hughes, AE Skeldon, P (2013) Grain-stored energy and the propagation of intergranular corrosion in AA2xxx aluminium alloys. Surf Interface Anal 45(10), 15431547.


Related content

Powered by UNSILO

An Examination of the Composition and Microstructure of Coarse Intermetallic Particles in AA2099-T8, Including Li Detection

  • Colin M. MacRae (a1), Anthony E. Hughes (a1) (a2) (a3), James S. Laird (a1), A. M. Glenn (a1), Nicholas C. Wilson (a1), Aaron Torpy (a1), Mark A. Gibson (a3) (a4), Xiaorong Zhou (a5), Nick Birbilis (a3) and George E. Thompson (a5)...


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.