In this study, AA2519 alloy was initially processed by multi axial forging (MAF) at room and cryogenic temperatures. Subsequently, the microstructure and the mechanical behavior of the processed samples under quasi-static loading were investigated to determine the influence of cryogenic forging on alloys’ subgrains dimensions, grain boundaries interactions, strength, ductility and toughness. In addition, the failure mechanisms at the tensile rupture surfaces were characterized using scanning electron micro-scope (SEM). The results show significant improvements in the strength, ductility and toughness of the alloy as a result of the cryogenic MAF process. The formation of nanoscale crystallite microstructure, heavily deformed grains with high density of grain boundaries and second phase breakage to finer particles were characterized as the main reasons for the increase in the mechanical properties of the cryogenic forged samples. The cryogenic processing of the alloy resulted in the formation of an ultrafine grained material with tensile strength and toughness that are ~41% and ~80% higher respectively after 2 cycles MAF when compared with the materials processed at ambient temperature. The fractography analysis on the tested materials shows a substantial ductility improvement in the cryoforged (CF) samples when compared to the room temperature forged (RTF) samples which is in alignment with their stress-strain profiles. However, extended forging at higher cycles than 2 cycles led only to increase in strength at the expense of ductility for both the CF and RTF samples.
References
[1]
Monteiro, W.A., da Silva, S.L.V., da Silva, L.V., de Andrade, A.H.P. and da Silva, L.C.E. (2017) Characterization of Nickel Alloy 600 with Ultra-Fine Structure Processed by Severe Plastic Deformation Technique (SPD). Journal of Materials Science and Chemical Engineering, 5, 33-44. https://doi.org/10.4236/msce.2017.54004
[2]
Zehetbauer, M.J. and Valiev, R.Z. (2006) Nanomaterials by Severe Plastic Deformation. John Wiley & Sons, Hoboken.
[3]
Berndt, N., Frint, P. and Wagner, M.F.-X. (2018) Influence of Extrusion Temperature on the Aging Behavior and Mechanical Properties of an AA6060 Aluminum Alloy. Metals, 8, 51. https://doi.org/10.3390/met8010051
[4]
Fritsch, S. and Wagner, M.F.-X. (2018) On the Effect of Natural Aging Prior to Low Temperature ECAP of a High-Strength Aluminum Alloy. Metals, 8, 63. https://doi.org/10.3390/met8010063
[5]
Nejadseyfi, O., Shokuhfar, A., Azimi, A. and Shamsborhan, M. (2015) Improving Homogeneity of Ultrafine-Grained/Nanostructured Materials Produced by ECAP Using a Bevel-Edge Punch. Journal of Materials Science, 50, 1513-1522. https://doi.org/10.1007/s10853-014-8712-3
[6]
Khabushan, J.K. and Bonabi, S.B. (2017) Investigating of the Microstructure and Mechanical Properties of Al-Based Composite Reinforced with Nano-Trioxide Tungsten via Accumulative Roll Bonding Process. Open Journal of Metal, 7, 9-23. https://doi.org/10.4236/ojmetal.2017.71002
[7]
Song, Y., Wang, W., Gao, D., Kim, H.-S., Yoon, E.-Y., Lee, D.-J., Lee, C.-S. and Guo, J. (2012) Inhomogeneous Hardness Distribution of High Pressure Torsion Processed IF Steel Disks. Materials Sciences and Applications, 3, 234-239. https://doi.org/10.4236/msa.2012.34034
[8]
Chen, Q., Shu, D., Hu, C., Zhao, Z. and Yuan, B. (2012) Grain Refinement in an As-Cast AZ61 Magnesium Alloy Processed by Multi-Axial Forging under the Multitemperature Processing Procedure. Materials Science and Engineering: A, 541, 98-104. https://doi.org/10.1016/j.msea.2012.02.009
[9]
Cherukuri, B. and Srinivasan, R. (2006) Properties of AA6061 Processed by Multi-Axial Compressions/Forging (MAC/F). Materials and Manufacturing Processes, 21, 519-525. https://doi.org/10.1080/10426910500471649
[10]
Bruder, E. (2018) Mechanical Properties of ARMCO® Iron after Large and Severe Plastic Deformation—Application Potential for Precursors to Ultrafine Grained Microstructures. Metals, 8, 191. https://doi.org/10.3390/met8030191
[11]
Panigrahi, S.K., Jayaganthan, R. and Chawla, V. (2008) Effect of Cryorolling on Microstructure of Al-Mg-Si Alloy. Materials Letters, 62, 2626-2629. https://doi.org/10.1016/j.matlet.2008.01.003
[12]
Magalhaes, D.C.C., Kliauga, A.M., Ferrante, M. and Sordi, V.L. (2017) Plastic Deformation of FCC Alloys at Cryogenic Temperature: The Effect of Stacking-Fault Energy on Microstructure and Tensile Behaviour. Journal of Materials Science, 52, 7466-7478. https://doi.org/10.1007/s10853-017-0979-8
[13]
Ahn, B. (2018) Synthesis and Properties of Bulk Nanostructured Metallic Materials. Metals, 8, 855. https://doi.org/10.3390/met8100855
[14]
Nejadseyfi, O., Shokuhfar, A., Dabiri, A. and Azimi, A. (2015) Combining Equal-Channel Angular Pressing and Heat Treatment to Obtain Enhanced Corrosion Resistance in 6061 Aluminum Alloy. Journal of Alloys and Compounds, 648, 912-918. https://doi.org/10.1016/j.jallcom.2015.05.177
[15]
Longtin, R., Hack, E., Neuenschwander, J. and Janczak-Rusch, J. (2011) Benign Joining of Ultrafine Grained Aerospace Aluminum Alloys Using Nano-technology. Advanced Materials, 23, 5812-5816. https://doi.org/10.1002/adma.201103275
[16]
Suryanarayana, C. (1994) Structure and Properties of Nanocrystalline Materials. Bulletin of Materials Science, 17, 307-346. https://doi.org/10.1007/BF02745220
[17]
Hansen, N. (2004) Hall-Petch Relation and Boundary Strengthening. Scripta Materialia, 51, 801-806. https://doi.org/10.1016/j.scriptamat.2004.06.002
[18]
Ivanov, K.V. and Naydenkin, E.V. (2012) Grain Boundary Sliding in Ultrafine Grained Aluminum under Tension at Room Temperature. Scripta Materialia, 66, 511-514. https://doi.org/10.1016/j.scriptamat.2011.12.039
[19]
Lee, Y.B., Shin, D.H., Park, K.-T. and Nam, W.J. (2004) Effect of Annealing Temperature on Microstructures and Mechanical Properties of a 5083 Al Alloy Deformed at Cryogenic Temperature. Scripta Materialia, 51, 355-359. https://doi.org/10.1016/j.scriptamat.2004.02.037
[20]
Vendra, S.S.L., Goel, S., Kumar, N. and Jayaganthan, R. (2017) A Study on Fracture Toughness and Strain Rate Sensitivity of Severely Deformed Al 6063 Alloys Processed by Multiaxial Forging and Rolling at Cryogenic Temperature. Materials Science and Engineering: A, 686, 82-92. https://doi.org/10.1016/j.msea.2017.01.035
[21]
Chen, Y.J., Roven, H.J., Gireesh, S.S., Skaret, P.C. and Hjelen, J. (2011) Quantitative Study of Grain Refinement in Al-Mg Alloy Processed by Equal Channel Angular Pressing at Cryogenic Temperature. Materials Letters, 65, 3472-3475. https://doi.org/10.1016/j.matlet.2011.07.067
[22]
Azimi, A., Shokuhfar, A. and Zolriasatein, A. (2014) Nanostructured Al-Zn-Mg-Cu-Zr Alloy Prepared by Mechanical Alloying Followed by Hot Pressing. Materials Science and Engineering: A, 595, 124-130. https://doi.org/10.1016/j.msea.2013.11.094
[23]
Azimi, A., Fallahdoost, H. and Nejadseyfi, O. (2015) Microstructure, Mechanical and Tribological Behavior of Hot-Pressed Mechanically Alloyed Al-Zn-Mg-Cu Powders. Materials & Design, 75, 1-8. https://doi.org/10.1016/j.matdes.2015.03.011
[24]
Tan, E., Kibar, A.A. and Gür, C.H. (2011) Mechanical and Microstructural Characterization of 6061 Aluminum Alloy Strips Severely Deformed by Dissimilar Channel Angular Pressing. Materials Characterization, 62, 391-397. https://doi.org/10.1016/j.matchar.2011.01.016
[25]
Adamczyk-Cieslak, B., Zdunek, J. and Mizera, J. (2016) Evolution of Microstructure and Precipitates in 2xxx Aluminum Alloy after Severe Plastic Deformation. IOP Conference Series: Materials Science and Engineering, 123, 1-4. https://doi.org/10.1088/1757-899X/123/1/012019
[26]
Azadmanjiri, J., Berndt, C.C., Kapoor, A. and Wen, C. (2015) Development of Surface Nano-Crystallization in Alloys by Surface Mechanical Attrition Treatment (SMAT). Critical Reviews in Solid State and Materials Sciences, 40, 164-181. https://doi.org/10.1080/10408436.2014.978446
[27]
Zuiko, I. and Kaibyshev, R. (2017) Deformation Structures and Strengthening Mechanisms in an Al-Cu Alloy Subjected to Extensive Cold Rolling. Materials Science and Engineering: A, 702, 53-64. https://doi.org/10.1016/j.msea.2017.07.001
[28]
Meyers, M.A., Mishra, A. and Benson, D.J. (2006) Mechanical Properties of Nanocrystalline Materials. Progress in Materials Science, 51, 427-556. https://doi.org/10.1016/j.pmatsci.2005.08.003
[29]
Pavlina, E.J. and Van Tyne, C.J. (2008) Correlation of Yield Strength and Tensile Strength with Hardness for Steels. Journal of Materials Engineering and Performance, 17, 888-893. https://doi.org/10.1007/s11665-008-9225-5
[30]
Queyreau, S., Monnet, G. and Devincre, B. (2010) Orowan Strengthening and Forest Hardening Superposition Examined by Dislocation Dynamics Simulations. Acta Materialia, 58, 5586-5595. https://doi.org/10.1016/j.actamat.2010.06.028
[31]
Valiev, R.Z., Alexandrov, I.V., Zhu, Y.T. and Lowe, T.C. (2002) Paradox of Strength and Ductility in Metals Processed Bysevere Plastic Deformation. Journal of Materials Research, 17, 5-8. https://doi.org/10.1557/JMR.2002.0002
[32]
Gong, Y.L., Wen, C.E., Li, Y.C., Wu, X.X., Cheng, L.P., Han, X.C. and Zhu, X.K. (2013) Simultaneously Enhanced Strength and Ductility of Cu-xGe Alloys through Manipulating the Stacking Fault Energy (SFE). Materials Science and Engineering: A, 569, 144-149. https://doi.org/10.1016/j.msea.2013.01.022
[33]
Das, P., Jayaganthan, R. and Singh, I.V. (2011) Tensile and Impact-Toughness Behaviour of Cryorolled Al 7075 Alloy. Materials & Design, 32, 1298-1305. https://doi.org/10.1016/j.matdes.2010.09.026
[34]
Rahmatabadi, D., Hashemi, R., Mohammadi, B. and Shojaee, T. (2017) Experimental Evaluation of the Plane Stress Fracture Toughness for Ultra-Fine Grained Aluminum Specimens Prepared by Accumulative Roll Bonding Process. Materials Science and Engineering: A, 708, 301-310. https://doi.org/10.1016/j.msea.2017.09.085
