Microstructure and mechanical properties of Al-5.8Mg-Mn-Sc-Zr alloy after annealing treatment

Abstract

An Al-5.8Mg-0.4Mn-0.35(Sc+Zr) (mass fraction, %) alloy sheet was prepared using water chilling copper mould ingot metallurgy processing which was protected by active flux. The influence of stabilizing annealing on mechanical properties and microstructure of the cold rolling sheet was studied. The results show that the strength and hardness of the alloy decrease, while the elongation increases with increasing the stabilizing annealing temperature. With the increase of stabilizing annealing time, the strength and hardness of the alloy drop slightly but its ductility exhibits no change. Partial recovery and recrystallization orderly occur with the increase of annealing temperature during stabilizing treatment. Only different degrees of recovery occur in the alloys annealed below 400 °C for 1 h. Partial recrystallization occurs after annealed at 450 °C for 1 h. By annealing at 300 °C for 1 h, the alloy can obtain the optimum application values of σ_b, σ_0.2 and δ, which are 436 MPa, 327 MPa and 16.7%, respectively.

Keywords

Al-Mg-Mn-Sc-Zr alloy / stabilizing treatment / Al₃(Sc, Zr) particle / microstructure / mechanical property

References

[1] LathabaiS., LloydP. G.. The effect of scandium on the microstructure, mechanical properties and weldability of a cast Al-Mg alloy [J]. Acta Materialia, 2002, 50(17): 4275-4292

[2] KumarN., MishraR. S., HuskampC., SankaranK. K.. Critical grain size for change in deformation behavior in ultrafine grained Al-Mg-Sc alloy [J]. Scripta Materialia, 2011, 64(6): 576-579

[3] LeeS., UtsunomiyaA., AkamatsuH., NeishiK., FurukawaM., HoritaZ., LangdonT. G.. Influence of scandium and zirconium on grain stability and superplastic ductilities in ultrafine-grained Al-Mg alloys [J]. Acta Materialia, 2002, 50(3): 553-564

[4] MaengD. Y., LeeJ. H., HongS. I.. The effect of transition elements on the superplastic behavior of Al-Mg alloys [J]. Materials Science and Engineering A, 2003, 357(1/2): 188-195

[5] DuG., YanD.-s., RongL.-jian.. Influence of intermediate annealing temperatures on mechanical properties of repeatedly cold-rolled Al-Mg-Sc-Zr alloy [J]. Acta Metallurgica Sinica, 2008, 44(10): 1209-1212

[6] HeZ.-bo.. Research on the structure and properties of welding joint for alloy Al-Mg-(Sc, Zr) [J]. Light Alloy Fabricaton Technology, 2006, 34(8): 44-47

[7] ChenS.-l., JiangF., YinZ.-m., LeiX.-f., NieBo.. Microstructure and properties of Al-Mg-Sc alloy weld joints filled with Al-Mg-Zr and Al-Mg-Zr-Sc weld wires [J]. The Chinese Journal of Nonferrous Metals, 2006, 16(5): 835-840

[8] PengY.-y., YinZ.-m., LeiX.-f., PanQ.-l., HeZ.-bo.. Microstructure and properties of friction stir welded joints of Al-Mg-Sc alloy plates [J]. Rare Metal Materials and Engineering, 2011, 40(2): 201-205

[9] RouminaR., SinclairC. W.. Recovery kinetics in the presence of precipitates: The softening response of an Al-Mg-Sc alloy [J]. Acta Materialia, 2010, 58(1): 111-121

[10] MarquisE. A., SeidmanD. N.. Coarsening kinetics of nanoscale Al₃Sc precipitates in an Al-Mg-Sc alloy [J]. Acta Materialia, 2005, 53(15): 4259-4268

[11] NieB., YinZ.-m., JiangF., JiangC.-l., CongF.-guan.. Influence of stabilizing annealing on tensile property and exfoliation corrosion resistance of Al-Mg-Sc alloy [J]. Transactions of Materials and Heat Treatment, 2008, 29(3): 58-61

[12] SmolaB., StulikovaI., OcenasekV., PelcovaJ., NeubertV.. Annealing effects in Al-Sc alloys [J]. Materials Science and Engineering A, 2007, 462(1/2): 370-374

[13] PengY.-y., YinZ.-m., YangJ., DuY.-xuan.. In-plane anisotropy of 1545 aluminum alloy sheet [J]. Transactions of Nonferrous Metals Society of China, 2005, 15(1): 87-92

[14] ChenX.-m., PanQ.-l., ZhouC.-r., YinZ.-min.. Effects of minor scandium addition on microstructure and tensile properties of Al-Mg-Mn alloy [J]. Chinese Journal of Rare Metals, 2003, 27(3): 403-405

[15] ClouetE., BarbuA., LaeL., MartinG.. Precipitation kinetics of Al₃Zr and Al₃Sc in aluminum alloys modeled with cluster dynamics [J]. Acta Materialia, 2005, 53(8): 2313-2325

[16] FazeliF., PooleW. J., SinclairC. W.. Modeling the effect of Al₃Sc precipitates on the yield stress and work hardening of an Al-Mg-Sc alloy [J]. Acta Materialia, 2008, 56(9): 1909-1918

[17] DuG., YangW., YanD.-s., RongL.-jian.. Precipitation behaviors of primary phases in Al-Mg-Sc-Zr aIloy [J]. The Chinese Journal of Nonferrous Metals, 2010, 20(6): 1083-1087

[18] MarquiesE. A., SeidmanD. N.. Nanoscale structural evolution of Al₃Sc precipitates in Al-Sc alloys [J]. Acta Materialia, 2001, 49(11): 1909-1919

[19] ZhaoW.-t., YanD.-s., RongL.-jian.. TEM observation of annealing microstructure of deformed Al-Mg-Sc-Zr alloy [J]. Acta Metallurgica Sinica, 2005, 41(11l): 1150-1154

[20] JiangF., WenK., JianH.-g., JiangC.-l., ZhaoJ., JiangLong.. Existing form and action mechanism of minor scandium and zirconium in Al-Cu-Mg alloy [J]. Journal of Central South University of Technology, 2010, 17(1): 19-23

[21] IwamurS., NakayamaM., MiursY.. Coherency between Al₃Sc precipitate and the matrix in Al alloys containing Sc [J]. Materials Science and Forum, 2002, 396(402): 1151-1156

[22] TangB.-y., LiD.-l., ChenP., YiJ.-x., WenL., PengL.-m., DingW.-jiang.. The thermal properties of Al-Mg-TM (TM=Sc, Zr): Ab initio study [J]. Solid State Sciences, 2010, 12(5): 845-850