PSI - Issue 50

Aleksandr Malikov et al. / Procedia Structural Integrity 50 (2023) 170–177 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Table 3 shows the average values obtained after tensile tests. In tensile tests with wire, the cross-sectional area was taken taking into account the height (thickness) of the rupture point.

Table 3. Mechanical characteristics of welded joints. Type

uts , MPa

σ ys , MPa

σ

δ, %

Alloy

434 351 382

265 241 262

7,2 3,9 4,5

Weld with wire

Weld with wire + post weld heat treatment

The tensile strength of the welded joint with wire after post-treatment increased by 31 MPa, the yield strength increased by 19 MPa, while the elongation at break decreased. 4. Conclusion. For the first time, based on an integrated approach that includes optimal laser welding with a wire, subsequent post-processing (hardening, plastic deformation and artificial aging), it was possible to implement a closed cycle of phase transformations in an aluminum-lithium alloy 1420 of the Al-Mg-Li system. It has been established that the strengthening phase δ'(Al3Li) is absent in the weld. The use of post -heat treatment in the form of hardening, followed by artificial aging, made it possible to form a strengthening phase δ'(Al3Li) in the weld. Post -processing restores the phase composition of the weld and thereby improves the mechanical characteristics. Acknowledgements The research was carried out within the state assignment of Ministry of Science and Higher Education of the Russian Federation (project No. 121030900259-0). The work was done at the shared research center SSTRC on the basis of the VEPP-4 - VEPP-2000 complex at BINP SB RAS 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. 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. Grushko, O., Ovsyannikov, B., Ovchinnokov, V., 2016. Aluminum- Lithium Alloys. CRC Press, Boca Raton : Taylor & Francis, CRC Press, 2017. Han, B., Tao, W., Chen, Y., Li, H., 2017. Double-sided laser beam welded T-joints for aluminum-lithium alloy aircraft fuselage panels: Effects of filler elements on microstructure and mechanical properties. Opt. Laser Technol. 93, 99 – 108. Katayama, S., 2013. Defect formation mechanisms and preventive procedures in laser welding, in: Handbook of Laser Welding Technologies. Elsevier, pp. 332 – 373. Malikov, A., Bulina, N., Sharafutdinov, M., Orishich, A., 2019. Study of the structure and phase composition of laser welded joints of Al-Cu-Li alloy under different heat treatment conditions. Int. J. Adv. Manuf. Technol. 104. https://doi.org/10.1007/s00170-019-04286-w Malikov, Alexander, Orishich, A., Bulina, N., Karpov, E., Sharafutdinov, M., 2019. Effect of post heat treatment on the phase composition and strength of laser welded joints of an Al – Mg – Li alloy. Mater. Sci. Eng. A 765, 138302. Malikov, A., Orishich, A., Vitoshkin, I., Bulina, N., Karpov, E., Gutakovskii, A., Batsanov, S., Ancharov, A., Tabakaev, R., 2021a. Effect of the structure and the phase composition on the mechanical properties of Al – Cu – Li alloy laser welds. Mater. Sci. Eng. A 809, 140947. Malikov, A., Orishich, A., Vitoshkin, I., Karpov, E., Ancharov, A., 2021b. Effect of post-heat treatment on microstructure and mechanical properties of laser welded Al-Cu-Mg alloy. J. Manuf. Process. 64, 620 – 632. Reference Ancharov, A.I., Manakov, A.Y., Mezentsev, N.A., Tolochko, B.P., Sheromov, M.A., Tsukanov, V.M., 2001. New station at the 4th beamline of the VEPP-3 storage ring. Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip. 470, 80 – 83.