Hot Torsion Tests of AA6082 Alloy

Abstract:

Materials characterization and the knowledge of their elastic-plastic behavior are of fundamental importance for the design of industrial manufacturing processes. Nowadays, FEM simulation is the main tool used to optimize product quality and minimize scraps, and the numerical codes have evolved over the years to obtain accurate solutions with reduced computational times. Nevertheless, in order to perform reliable simulations, it is necessary to include accurate modeling of the material flow stress. Hot torsion is a powerful method for the characterization of the material flow stress because, tests can be carried out at constant speeds and temperatures, reaching large strain values, and thus getting over the limits of compression and tensile tests. In this paper the hot torsion characterization applied to AA6082 alloy is presented: tests were performed with equivalent strain rates of 0.01, 0.1, 1, and 10 s^-1, in the temperature range from 440 to 550 °C (from 713.15 to 823.15 K). The results are presented in terms of equivalent stress vs equivalent strain. Finally, the material flow stress curve was predicted by the Hyperbolic sine model and Hensel-Spittel law, and the material parameters A, m_1-9 are provided for the temperature expressed in °C and K.

• Periodical: Key Engineering Materials (Volume 988)
• Pages: 21-29
• DOI: https://doi.org/10.4028/p-5c0LIi
• Online since: September 2024
• Authors: Sara Di Donato*, Riccardo Pelaccia, Marco Negozio, Mohamad El Mehtedi, Barbara Reggiani, Lorenzo Donati
• Keywords: AA6082, Aluminum, Flow Stress, Hot Torsion Test, Material Characterization

References

[1] L. Donati, B. Reggiani, R. Pelaccia, M. Negozio, S. Di Donato, Advancements in extrusion and drawing: a review of the contributes by the ESAFORM community, International Journal of Material 15 41 (2022).

DOI: 10.1007/s12289-022-01664-w

[2] L. Donati, A. Segatori, M. El Mehtedi, L. Tomesani, Grain evolution analysis and experimental validation in the extrusion of 6XXX alloys by use of a lagrangian FE code, International Journal of Plasticity 46 (2013) 70-81.

DOI: 10.1016/j.ijplas.2012.11.008

[3] R. Pelaccia, B. Reggiani, M. Negozio, L. Donati, Liquid nitrogen in the industrial practice of hot aluminium extrusion: experimental and numerical investigation, Int J Adv Manuf Technol 119 (2022) 3141-3155.

DOI: 10.1007/s00170-021-08422-3

[4] M. Negozio, R. Pelaccia, L. Donati, B. Reggiani, FEM Analysis of the Skin Contamination Behavior in the Extrusion of a AA6082 Profile, Key Engineering Materials Trans Tech Publications Ltd. (July 22, 2022).

DOI: 10.4028/p-y37nm3

[5] R. Pelaccia, B. Reggiani, M. Negozio, S. Di Donato, L. Donati, Investigation on the topological optimization of cooling channels for extrusion dies, Materials Research Proceedings 28 (2023) 533-542.

DOI: 10.21741/9781644902479-58

[6] I. Kniazkin, R. Pelaccia, M. Negozio, S. Di Donato, L. Donati, B. Reggiani, N. Biba, R. Rezvykh, I. Kulakov, Investigation of the skin contamination predictability by means of QForm UK extrusion code, Materials Research Proceedings 28 (2023) 543-552.

DOI: 10.21741/9781644902479-59

[7] M. Negozio, L. Donati, R. Pelaccia, B. Reggiani, S. Di Donato, Experimental analysis and modeling of the recrystallization behaviour of a AA6060 extruded profile, Materials Research Proceedings 28 (2023) 477-486.

DOI: 10.21741/9781644902479-52

[8] M. Negozio, R. Pelaccia, L. Donati, B. Reggiani, Simulation of the microstructure evolution during the extrusion of two industrial-scale AA6063 profiles, Journal of Manufacturing Processes 99 (2023) 501-512.

DOI: 10.1016/j.jmapro.2023.05.075

[9] F. Garofalo, An empirical relation defining the stress dependence of minimum creep rate in metals, Transactions of the Metallurgical Society of Aime 227 (April 1963) 351-356.

[10] C.M. Sellars, WJ McG Tegart, Memoires Scientifique Rev. Metallurg. 58 9 (1966) 731.

[11] G.E. Dieter, S.L. Semiatin, H.A. Kuhn, Handbook of Workability and Process Design, ASM International publications United States of America (2003) 86-127.

[12] L. Donati, M. El Mehtedi, Characterization of Flow Stress of Different AA6082 Alloys By Means Of Hot Torsion Test, AIPConf Proc 1353 (2011) 455-460.

DOI: 10.1063/1.3589557

[13] M. El Mehtedi, S. Spigarelli, F. Gabrielli, L. Donati, Comparison Study of Constitutive Models in Predicting the Hot Deformation Behavior of AA6060 and AA6063 Aluminium Alloys, Materials Today: Proceedings 2 10 Part A (2015) 4732-4739.

DOI: 10.1016/j.matpr.2015.10.006

[14] A. Hensel, T. Spittel, Kraft- und Arbeitsbedarf bildsamer Formgebungsverfahren, Deutscher Verlag für Grundstoffindustrie: Leipzig, Germany (1978) 336-360.

[15] G.R. Canova, U.F. Kocks, J.J. Jonas, Theory of torsion texture development, Acta metall. 32 2 (1984) 211-226.

DOI: 10.1016/0001-6160(84)90050-6

[16] A. Gräber, K. Pöhlandt, State of the art of the torsion test for determining flow curves, Steel Res. 61 (1990) 212-218.

DOI: 10.1002/srin.199000334

[17] D.S. Fields, W.A. Backofen, Determination of strain-hardening characteristics by torsion testing, 57 (1957) 1259-1272.

[18] B. Verlinden, A. Suhadi, L. Delaey, A generalized constitutive equation for an AA6060 Aluminium alloy, Scripta Metallurgica et Materialia 28 11 (1993) 1441-1446.

DOI: 10.1016/0956-716x(93)90496-f

[19] S. Spigarelli, E. Evangelista, H.J. McQueen, Study of hot workability of a heat treated AA6082 aluminum alloy, Scripta Materialia 49 (2003) 179-183.

DOI: 10.1016/s1359-6462(03)00206-9

[20] X. Chen,Y. Du, K. Du, T. Lian, B. Liu, Z. Li, X. Zhou, Identification of the Constitutive Model Parameters by Inverse Optimization Method and Characterization of Hot Deformation Behavior for Ultra-Supercritical Rotor Steel, Materials 14 8 (2021) 1958.

DOI: 10.3390/ma14081958

[21] H. Wang, W. Wang, R. Zhai, R. Ma, J. Zhao, Z. Mu, Constitutive Equations for Describing the Warm and Hot Deformation Behavior of 20Cr2Ni4A Alloy Steel, Metals. 10 9 (2020) 1169.

DOI: 10.3390/met10091169