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On the Combined Role of Strain Hardening and Strain Rate on the Degree of Heterogeneity of Plastic Flow in an Al-2.5%Mg Alloy

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Abstract

Jerky flow due to the Portevin-Le Chatelier (PLC) effect is investigated in an Al-2.5%Mg alloy loaded in tension under constant driving velocity at room temperature. We analyzed the strain and strain rate dependences of the characteristics of the PLC instabilities, such as the type of instability, the magnitude of the stress drops and the critical plastic strain for the onset of unstable plastic flow. The study shows the combined role of strain hardening and applied strain rate on instability which can lead to transitions between types of instability. Work hardening and applied strain rate reduction promote Dynamic Strain Aging (DSA) and consequently lead to intensification of strain localizations. The results suggest that pipe diffusion mechanism of solute Mg atoms, through forest dislocation cores, is more relevant than bulk diffusion mechanism in our experiments conditions. It is shown that, when all mobile dislocations perform a successful activation event, the resulting elementary incremental strain also depends on the applied strain rate. Only the strain dependence of this concept is taken into account by most DSA models to describe plastic instabilities.

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REFERENCES

  1. K. Chihab, Y. Estrin, L.P. Kubin, and J. Vergnol, “The kinetics of the Portevin-Le Chatelier bands in an Al-5at%Mg alloy,” Scripta Metall. 21, 203–208 (1987). https://doi.org/10.1016/0036-9748(87)90435-2

    Article  Google Scholar 

  2. H. Ait-Amokhtar, S. Boudrahem, and C. Fressengeas, “Spatiotemporal aspects of jerky flow in Al-Mg alloys, in relation with the mg content,” Scripta Mater. 54, 2113–2118 (2006). https://doi.org/10.1016/j.scriptamat.2006.03.006

    Article  Google Scholar 

  3. H. Ait-Amokhtar, C. Fressengeas, and S. Boudrahem, “The dynamics of Portevin-Le Chatelier bands in an Al-Mg alloy from infrared thermography,” Mater. Sci. Eng. A. 488, 540–546 (2008). https://doi.org/10.1016/j.msea.2007.11.075

    Article  Google Scholar 

  4. S. Dahdouh, M. Mehenni, and H. Ait-Amokhtar, “Kinetics of formation and propagation of type A Portevin-Le Chatelier bands in the presence of a small circular hole,” J. Alloys Compd. 885C, 160982 (2021). https://doi.org/10.1016/j.jallcom.2021.160982

  5. L.P. Kubin and Y. Estrin, “Dynamic strain ageing and the mechanical response of alloys,” J. Phys. III France. 1, 929–943 (1991). https://doi.org/10.1051/jp3:1991166

    Article  Google Scholar 

  6. L. Z. Mansouri, J. Coër, S. Thuillier, et al., “Investigation of Portevin- Le Châtelier effect during Erichsen test,” Int. J. Mater. Form. 13, 687–697 (2020). https://doi.org/10.1007/s12289-019-01511-5

    Article  Google Scholar 

  7. P. G. McCormick, “A model for the Portevin-Le Chatelier effect in substitutional alloys,” Acta Metall. 20, 351–354 (1972). https://doi.org/10.1016/0001-6160(72)90028-4

    Article  Google Scholar 

  8. Van Den Beukel, “Theory of the effect of dynamic strain aging on mechanical properties,” Phys. Stat. Sol. (a) 30, 197–206 (1975). https://doi.org/10.1002/pssa.2210300120

    Article  ADS  Google Scholar 

  9. L.P. Kubin, C. Fressengeas, and G. Ananthakrishna, “Collective behavior of dislocation in plasticity,” in Dislocations in Solids, Ed. by F. R. N. Nabarro and M. S. Duesbery (Elsevier, Amsterdam, 2001), pp. 101–192. https://doi.org/10.1016/S1572-4859(02)80008-0

    Book  Google Scholar 

  10. C. Fressengeas, A. J. Beaudoin, M. Lebyodkin, et al., “Dynamic strain aging: A coupled dislocation-Solute dynamic model,” Mater. Sci. Eng. A. 400–401, 226–230 (2005).https://doi.org/10.1016/j.msea.2005.02.073

  11. G. G. Saha, P. G. McCormick, and P. Rama Rao, “Portevin-Le Chatelier effect in an Al-Mn alloys I: serration characteristics mater,” Mater. Sci. Eng. 62, 187–196 (1984). https://doi.org/10.1016/0025-5416(84)90221-0

    Article  Google Scholar 

  12. P. G. McCormick, “Theory of flow localisation due to dynamic strain ageing,” Acta Metall. 36, 3061-3067 (1988). https://doi.org/10.1016/0001-6160(88)90043-0

    Article  Google Scholar 

  13. L. P. Kubin and Y. Estrin, “Evolution of dislocation densities and the critical conditions for the Portevin-Le Chatelier effect,” Acta Metall. Mater. 38, 697–708 (1990). https://doi.org/10.1016/0956-7151(90)90021-8

    Article  Google Scholar 

  14. E. Pink and A. Grinberg, “Stress drops in serrated flow curves of A15Mg,” Acta Metall. 30, 2153–2160 (1982). https://doi.org/10.1016/0001-6160(82)90136-5

    Article  Google Scholar 

  15. J. M. Robinson, “In-situ deformation of aluminium alloy polycrystals observed by high-voltage electron microscopy,” Mater. Sci. Eng. A 203, 238–245 (1995). https://doi.org/10.1016/0921-5093(95)09849-6

    Article  Google Scholar 

  16. L. Ziani, S. Boudrahem, H. Ait-Amokhtar, et al., “Unstable plastic flow in the Al-2%Mg alloy,” Mater. Sci. Eng. A. 536, 239–243 (2012). https://doi.org/10.1016/j.msea.2012.01.004

    Article  Google Scholar 

  17. H. Ait-Amokhtar, C. Fressengeas, and K. Bouabdallah, “On the effects of the Mg content on the critical strain for the jerky flow of Al–Mg alloys,” Mater. Sci. Eng. A. 631, 209–213 (2015). https://doi.org/10.1016/j.msea.2015.02.055

    Article  Google Scholar 

  18. A. H. Cottrell and B. A. Bilby, “Dislocation theory of yielding and strain ageing of iron,” Proc. Phys. Soc. 62, 49–62 (1949). https://doi.org/10.1088/0370-1298/62/1/308

    Article  ADS  Google Scholar 

  19. Ch. Schwink and A. Nortmann, “Present experimental Knowledge of dynamic strain ageing fcc solid solutions,” Mater. Sci. Eng A. 234–236, 1–7 (1997). https://doi.org/10.1016/S0921-5093(97)00139-1

  20. N. Chibane, H. Ait-Amokhtar, and C. Fressengeas, “On the strain rate dependence of the critical strain for plastic instabilities in Al-Mg alloys,” Scripta Mater. 130, 252–255 (2017). https://doi.org/10.1016/j.scriptamat.2016.11.037

    Article  Google Scholar 

  21. T. Böhlke, G. Bondár, Y. Estrin, and M.A. Lebyodkin, “Geometrically non-linear modeling of the Portevin–Le Chatelier effect,” Comp. Mater Sci. 44, 1076–1088 (2009). https://doi.org/10.1016/j.commatsci.2008.07.036

    Article  Google Scholar 

  22. M.Mehenni,H.Ait-Amokhtar,and C.Fressengeas, “Spatiotemporal correlations in the Portevin-Le Chatelier band dynamics during the type B - type C transition,” Mater. Sci. Eng A. 756, 313-318 (2019). https://doi.org/10.1016/j.msea.2019.04.036

    Article  Google Scholar 

  23. R. Král, and P. Lukáč, “Modelling of strain hardening and its relation to the onset of Portevin-Le Chatelier effect in Al-Mg alloys,” Sci. Eng. A. 234-236, 786–789 (1997). https://doi.org/10.1016/S0921-5093(97)00327-4

    Article  Google Scholar 

  24. J. Balík, P. Lukác, and L. P. Kubin, “Inverse critical strains for jerky flow in al-Mg alloys,” Scripta Mater. 42, 465–471 (2000). https://doi-org.sndl1.arn.dz/10.1016/S1359-6462(99)00373-5

    Article  Google Scholar 

  25. Y. Brechet and Y. Estrin, “On the influence of precipitation on the Portevin-Le Chatelier effect,” Acta Metall. Mater. 43, 955-963 (1995). https://doi.org/10.1016/0956-7151(94)00334-E

    Article  Google Scholar 

  26. N. Chibane and H. Ait-Amokhtar, “On the Portevin-Le Chatelier instabilities in the industrial Al-2.5% Mg alloy,” in CFM 2013-21 ème Congrès Français de Mécanique (Bordeaux, France, 2013), pp. 1–5. http://hdl.handle.net/2042/52385

  27. H. Ait-Amokhtar, P. Vacher, and S. Boudrahem, “Kinematics fields and spatial activity of Portevin-Le Chatelier bands using the digital image correlation method,” Acta Mater. 54, 4365–4371 (2006). https://doi.org/10.1016/j.actamat.2006.05.028

    Article  ADS  Google Scholar 

  28. H. Ait-Amokhtar and C. Fressengeas, “Crossover from continuous to discontinuous propagation in the Portevin-Le Chatelier effect,” Acta Mater. 58, 1342–1349 (2010). https://doi.org/10.1016/j.actamat.2009.10.038

    Article  ADS  Google Scholar 

  29. M. S. Bharathi, M. Lebyodkin, G. Ananthakrishna, et al., “The hidden order behind jerky flow,” Acta Mater. 50, 2813–2824 (2002). https://doi.org/10.1016/S1359-6454(02)00099-X

    Article  ADS  Google Scholar 

  30. H. Chen, Z. Chen, Y. Chen, et al., “Effects of nanosized precipitates on the Portevin-Le Chatelier behavior: Model prediction and experimental verification,” Materialia 21, 101299 (2022). https://doi.org/10.1016/j.mtla.2021.101299

  31. G. Horváth, N. Q. Chinh, J. Gubicza, and J. Lendvai, “Plastic instabilities and dislocation densities during plastic deformation in Al–Mg alloys,” Mater. Sci. Eng. 445–446, 186–192 (2007). https://doi-org.sndl1.arn.dz/10.1016/j.msea.2006.09.019

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Funding

H. Ait-Amokhtar is thankful to the University of Bejaia (Algeria) for financial support (PRFU N°B00L02UN060120190002).

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Correspondence to Samir Dahdouh.

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Dahdouh, S., Ait-Amokhtar, H. & Sadeddine, A. On the Combined Role of Strain Hardening and Strain Rate on the Degree of Heterogeneity of Plastic Flow in an Al-2.5%Mg Alloy. Mech. Solids 57, 1550–1560 (2022). https://doi.org/10.3103/S002565442206019X

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