Journals →  Tsvetnye Metally →  2016 →  #9 →  Back

MATERIALS SCIENCE
ArticleName Structure and mechanical properties of new aluminium-lithium alloy plates with high fracture toughness
DOI 10.17580/tsm.2016.09.12
ArticleAuthor Ryabova E. N., Kolobnev N. I., Khokhlatova L. B., Oglodkov M. S.
ArticleAuthorData

All-Russian Scientific Research Institute of Aviation Materials, Moscow, Russia:

E. N. Ryabova, Engineer, e-mail: journal@viam.ru
N. I. Kolobnev, Chief Researcher
L. B. Khokhlatova, Head of a Sector
M. S. Oglodkov, Senior Researcher

Abstract

We investigated the mechanical properties, tensile, impact toughness, fracture toughness, and phase composition of cold-rolled experimental-industrial plates, made of a new Al – Cu – Li alloy with Ag, Sc, Mg and Zn additives after different heat treatment. The hardening heat temperature was (530±3) оС, and its holding period was 15–20 minutes. The plates were stretch flattened with a permanent form change for 0.5–0.8% after quenching. The quenching treatment schedule was the same as for the industrial Al – Cu – Li alloys. The phase and microstructure analysis were made in wide time-temperature area from 120 to 170 оС for 10–60 hours on JEM200CX (EM 1132039–49) transmission electron microscope (according to MM 1.595-17-344–2007). The tensile properties, KCU and fracture toughness were defined in the plate-made L and L – T transverses samples. The tensile tests at the room temperature were made using Zwick Roell Z100 testing machine according to the standard GOST 1497–84. The fracture toughness tests at the room temperature were made using MTS-100 testing machine according to the standard GOST 25.506–85. Alloy`s phase composition analysis showed that T1 ′, θ and S precipitations exist at almost all time-temperature aging area from 130 to 160 оC for 20 to 60 hours. The maximum strength was reached at 160 оC (σb≥525 МPа, σ0.2480 МPа). The best combination of impact strength, fracture toughness and strength characteristics was reached at 140–150 оС temperature: КСU = 200 kJ/m, Ксу = 95 МPa√m (В = 200 мм), σu490 MPа, σ0.2450 МPа, which is caused by the precipitation morphology of presented T1 (Al2CuLi), S′ (Al2CuMg), θ′ (Al2Cu) phases at the same time.
The investigation was made in the framework of implementation of an 8.1 integral research area: high-strength weldable aluminum alloys and low-density aluminum-lithium alloys with high fracture toughness (“Strategic orientations of materials, treatment processes development for the period to 2030”).

keywords Aluminium alloys, impact elasticity, mechanical properties, thermal treatment, phase composition, fracture toughness, microstructure
References

1. Kablov E. N. Innovatsionnye razrabotki federalnogo gosudarstvennogo unitarnogo predpriyatiya “VIAM” gosudarstvennogo nauchnogo tsentra Rossiyskoy Federatsii po realizatsii “Strategicheskikh napravleniy razvitiya materialov i tekhnologiy ikh pererabotki na period do 2030 goda” (Innovative developments of FSUE “VIAM” SSC of RF on realization of “Strategic directions of the development of materials and technologies of their processing for the period until 2030”). Aviatsionnye materialy i tekhnologii = Aviation Materials and Technologies. 2015. No. 1 (34). pp. 3–33.
2. Antipov V. V., Kolobnev N. I., Khokhlatova L. B. Razvitie alyuminiy-litievykh splavov i mnogostupenchatykh rezhimov termicheskoy obrabotki (Development of Aluminium-Lithium Alloys and Multistage Heat Treatment Conditions). Aviatsionnye materialy i tekhnologii = Aviation Materials and Technologies. 2012. No. S. pp. 183–195.
3. Kablov E. N. Aviakosmicheskoe materialovedenie (Aerospace materials science). Vse materialy. Entsiklopedicheskiy spravochnik = Polymer Science. Series D. 2008. No. 3. pp. 2–14.
4. Magnusen P. E., Mooy D. C., Yocum L. A., Rioja R. J. Development of high toughness sheet and extruded products for airplane fuselage structures. The Minerals, Metals and Materials Society. 2012. pp. 535–540.
5. Karabin L. M., Bray G. H., Rioja R. L., Venema G. Al – Li – Cu – Mg – (Ag) products for lower wing skin applications. The Minerals, Metals and Materials Society. 2012. pp. 529–534.
6. Dorin T., Deschamps A., Geuser F. D., Weyland M. Quantitative description of the T1 morphology and strengthening mechanisms in an age-hardenable Al – Li – Cu alloy. The Minerals, Metals and Materials Society. 2012. pp. 1155–1160.
7. Bes B., Ribes H., Sigli C., Warner T. High fracture toughness aluminumcopper-lithium sheet or light-gauge plate suitable for use in a fuselage panel. Patent US, No. 687444. Published: 29.06.2010.
8. Klochkova Yu. Yu., Grushko O. E, Lantsova L. P., Burlyaeva I. P., Ovsyannikov B. V. Osvoenie v promyshlennom proizvodstve polufabrikatov iz perspektivnogo alyuminiylitievogo splava V-1469 (Mastering of semifinished products, produced of V-1469 (B-1469) Al – Li advanced alloy in the commercial production). Aviatsionnye materialy i tekhnologii = Aviation Materials and Technologies. 2011. No. 1. pp. 8–12.
9. Klochkov G. G., Grushko O. E., Klochkova Yu. Yu., Romanenko V. Yu. Promyshlennoe osvoenie vysokoprochnogo splava V-1469 sistemy Al – Cu – Li –Mg (Industrial development of high-strength alloy V-1469 (B-1469) of Al –Cu – Li – Mg system). Trudy Vserossoyskogo instituta aviatsionnykh materialov = Proceedings of VIAM. 2014. No. 7. p. 01. Available at : http://viamworks.ru/plugins/content/journal/uploads/articles/pdf/680.pdf

10. Kablov E. N., Antipov V. V., Senatorova O. G., Lukina N. F. Novyy klass sloistykh alyumostekloplastikov na osnove alyuminiy-litievogo splava 1441 s ponizhennoy plotnostyu (New type of aluminium fiberglass laminates on the basis of low density 1441 aluminium-lithium alloy). Vestnik MGTU imeni N. E. Baumana. Seriya “Mashinostroenie” = Herald of the Bauman Moscow State Technical University. Series Mechanical Engineering. 2011. No. SP2. pp. 174–183.
11. Kolobnev N. I. Istoriya razvitiya, fazovyy sostav i svoystva splavov sistemy Al – Cu – Li (Developmental Histroy, Phase Composition and Properties of Al – Cu – Li Alloys). Tekhnologiya legkikh splavov = Technology of Light Alloys. 2015. No. 2. pp. 46–52.
12. Gumbmann E., Geuser F., Lefebvre W., Sigli Ch., Deschamps A. The influence of Mg and Ag on the precipitation kinetics and the formation of the T1 phase in Al – Cu – Li alloys. Conference proceedings of 14th International Conference on Aluminium Alloys (ICAA14). 2014. pp. 945–950.
13. Ryabova E. N., Kolobnev N. I., Khokhlatova L. B., Oglodkov M. S. Osobennosti struktury i svoystv listov iz splavov sistemy Al – Cu – Li – Mg (Features of structure and properties of Al – Cu – Li – Mg plates). Metallurgiya mashinostroeniya = Metallurgy of Machinery Building. 2015. No. 1. pp. 17–19.
14. Zakharov V. V. Strukturno uprochnennye alyuminievye splavy (Structurallyreinforced aluminium alloys). Tekhnologiya legkikh splavov = Technology of Light Alloys. 2009. No. 2. pp. 21–29.
15. GOST 1497–84. Metally. Metody ispytaniy na rastyazhenie (State Standard 1497–84. Metals. Methods of tension test). Introduced: 1986–01–01. (in Russian) 

16. GOST 25.506–85. Raschety ispytaniya na prochnost. Metody mekhanicheskikh ispytaniy metallov. Opredelenie kharakteristik treshchinostoykosti (vyazkosti razrusheniya) pri staticheskom nagruzhenii (State Standard 25.506–85. Design, calculation and strength testing. Methods of mechanical testing of metals. Determination of fracture toughness characteristics under the static loading). Introduced: 1986–01–01. (in Russian)
17. Kablov E. N., Kolobnev N. I., Antipov V. V., Khokhlatova L. B., Vershinina E. N., Oglodkov M. S. Splav na osnove sistemy Al – Cu – Li i izdelie, vypolnennoe iz nego (Al – Cu – Li alloy and its product). Patent RF, No. 2560481. Applied: 01.07.2014. Published: 20.08.2015. Bulletin No. 23.

Language of full-text russian
Full content Buy
Back