Abstract
Aluminium–lithium (Al-Li) alloys are very attractive for aerospace applications due to their outstanding properties, such as high specific strength, high rigidity and good resistance to corrosion and fatigue, compared to conventional aluminium alloys. The butt joints of Al-Li 2A97-T3 alloy sheet produced by fibre laser welding with ER2319 filler wire were investigated in this paper. Uniaxial tensile tests have been performed to determine the nominal mechanical properties of the joints with and without porosities. In addition, a defect zone was defined in the welded specimens to investigate the effects of porosity on the joint tensile behaviour. The post-weld strength prediction (PWSP) model in a previous study has been extended by including the effects of the porosity in the welds to predict the overall response of the butt joints. The experimental and the modelling results show a good agreement, with the yield strength having a deviation lower than 5%. Both the yield strength and the ductility of the tensile specimens were observed to have decreased with the presence of porosities. The porosities aggravated the inhomogeneous deformation in the weld zone. Higher strain rate was found in the defect area than the remaining weld zone during plastic deformation, as the porosity in the specimen caused inhomogeneous deformation. It was found that this accelerated the failure of the specimen and lowered the global ductility significantly.
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Sundaresan S, Janaki Ram GD, Murugesan R, Viswanathan N (2000) Combined effect of inoculation and magnetic arc oscillation on microstructure and tensile behaviour of type 2090 Al–Li alloy weld fusion zones. Sci Technol Weld Joi 5:257–264
Kostrivas A, Lippold JC (1999) Weldability of Li-bearing aluminium alloys. Int Mater Rev 44:217–237
Hector LG, Chen Y-L, Agarwal S, Briant CL (2004) Texture characterization of autogenous Nd:YAG laser welds in AA5182-O and AA6111-T4 aluminum alloys. Metall Mater Trans A 35:3032–3038
Peng Y, Fu Z, Wang W, Zhang J, Wang Y, Wang H, Zhang Q (2008) Phase transformation at the interface during joining of an Al–Mg–Li alloy by pulsed current heating. Scripta Mater 58:49–52
Padmanabham G, Pandey S, Schaper M (2005) Pulsed gas metal arc welding of Al–Cu–Li alloy. Sci Technol Weld Joi 10:67–75
Solórzano IG, Darwish FA, de Macedo MC, de Menezes SO (2003) Effect of weld metal microstructure on the monotonic and cyclic mechanical behavior of tig welded 2091 Al–Li alloy joints. Mater Sci Eng A 348:251–261
Li S, Chen G, Zhou C (2015) Effects of welding parameters on weld geometry during high-power laser welding of thick plate. Int J Adv Manuf Tech 79:177–182
Luo Y, Tang X, Lu F (2014) Experimental study on deep penetrated laser welding under local subatmospheric pressure. Int J Adv Manuf Tech 73:699–706
Hamidinejad SM, Hasanniya MH, Salari N, Valizadeh E (2013) CO2 laser welding of interstitial free galvanized steel sheets used in tailor welded blanks. Int J Adv Manuf Tech 64:195–206
Ion JC (2000) Laser beam welding of wrought aluminium alloys. Sci Technol Weld Joi 5:265–276
Zhao H, White DR, DebRoy T (1999) Current issues and problems in laser welding of automotive aluminium alloys. Int Mater Rev 44:238–266
Williams JC, Starke EA Jr (2003) Progress in structural materials for aerospace systems1. Acta Mater 51:5775–5799
Chen H-C, Pinkerton AJ, Li L (2011) Fibre laser welding of dissimilar alloys of Ti-6Al-4V and Inconel 718 for aerospace applications. Int J Adv Manuf Tech 52:977–987
Brenner B, Standfuß J, Dittrich D, Winderlich B, Liebscher J, Hackius J (2008) Laser beam welding of aircraft fuselage structures, International Congress on Applications of Lasers & Electro Optics (ICALEO). Temecula, USA
Mueller-Hummel P, Ferstl S, Sengotta M, Lang R (2003) Laser beam welding of high stressed, complex aircraft structural parts. First International Symposium on High-Power Laser Macroprocessing, Osaka
Xu F, Chen L, Li SG, LI XY, Yang J (2011) Microstructure and mechanical properties of Al-Li alloy by laser welding with filler wire. Rare Metal Mat Eng 40:1775–1779
Cui L, Li X, He D, Chen L, Gong S (2012) Effect of Nd:YAG laser welding on microstructure and hardness of an Al–Li based alloy. Mater Charact 71:95–102
Matsunawa A (2001) Problems and solutions in deep penetration laser welding. Sci Technol Weld Joi 6:351–354
Zhang X, Yang W, Xiao R (2015) Microstructure and mechanical properties of laser beam welded Al–Li alloy 2060 with Al–Mg filler wire. Mater Design 88:446–450
Fu B, Qin G, Meng X, Ji Y, Zou Y, Lei Z (2014) Microstructure and mechanical properties of newly developed aluminum–lithium alloy 2A97 welded by fiber laser. Mater Sci Eng A 617:1–11
Wu SC, Yu C, Zhang WH, Fu YN, Helfen L (2015) Porosity induced fatigue damage of laser welded 7075-T6 joints investigated via synchrotron X-ray microtomography. Sci Technol Weld Joi 20:11–19
Çam G, İpekoğlu G (2017) Recent developments in joining of aluminum alloys. Int J Adv Manuf Tech 91:1851–1866
Xiao R, Wuxiong Y, Kai C (2007) Porosity characterization in laser welds of Al-Li alloy 1420. Appl Laser 27:13–17
Kai C, Wuxiong Y, Rongshi X (2010) Direct laser welding for Al-Li alloy plate without the cleaning of surface film. Springer, London
Whitaker IR, McCartney DG, Calder N, Steen WM (1993) Microstructural characterization of CO2 laser welds in the Al-Li based alloy 8090. J Mater Sci 28:5469–5478
Matsunawa A, Mizutani M, Katayama S, Seto N (2003) Porosity formation mechanism and its prevention in laser welding. Weld Int 17:431–437
Matsunawa A, Kim J-D, Seto N, Mizutani M, Katayama S (1998) Dynamics of keyhole and molten pool in laser welding. J Laser Appl 10:247–254
Seto N, Katayama S, Mizutani M, Matsunawa A (2000) Relationship between plasma and keyhole behavior during CO2 laser welding. High-Power Lasers in Manufacturing, Osaka
Abdullah K, Wild PM, Jeswiet JJ, Ghasempoor A (2001) Tensile testing for weld deformation properties in similar gage tailor welded blanks using the rule of mixtures. J Mater Process Tech 112:91–97
Liu S, Chao YJ (2005) Determination of global mechanical response of friction stir welded plates using local constitutive properties. Model Simul Mater Sci Eng 13:1–15
Lockwood WD, Tomaz B, Reynolds AP (2002) Mechanical response of friction stir welded AA2024: experiment and modeling. Mater Sci Eng A 323:348–353
GOM (2007) ARAMIS user manual. GOM mbH, Braunschweig
DebRoy T, David SA (1995) Physical processes in fusion welding. Rev Mod Phys 67:85–112
Lee MF, Huang JC, Ho NJ (1996) Microstructural and mechanical characterization of laser-beam welding of a 8090 Al-Li thin sheet. J Mater Sci 31:1455–1468
Liu J, Wang L, Lee J, Chen R, El-Fakir O, Chen L, Lin J, Dean TA (2015) Size-dependent mechanical properties in AA6082 tailor welded specimens. J Mater Process Tech 224:169–180
Hosford WF (2005) Mechanical behavior of materials. UK, Cambridge
Funding
The authors would like to acknowledge the support from Aviation Industry Corporation of China (AVIC) Beijing Aeronautical Manufacturing Technology Research Institute for this funded research. The research was performed at the AVIC Centre for Structural Design and Manufacture at Imperial College London.
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He, E., Liu, J., Lee, J. et al. Effect of porosities on tensile properties of laser-welded Al-Li alloy: an experimental and modelling study. Int J Adv Manuf Technol 95, 659–671 (2018). https://doi.org/10.1007/s00170-017-1175-3
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DOI: https://doi.org/10.1007/s00170-017-1175-3