采用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和室温拉伸试验研究了稀土Nd对热挤压Mg-5.0Y-xNd-0.6Zr(x=0,1.0,2.6,4.2,质量分数/%,下同)合金微观组织和力学性能的影响。结果表明:随着Nd加入量增大,挤压合金中带状分布的β和Mg24Y5相颗粒增多,促进了动态再结晶的形核,提高了再结晶体积分数,其平均晶粒尺寸由4.5μm细化到2.6μm。挤压合金的抗拉强度和屈服强度随着Nd加入量增大而升高,最高分别达到303 MPa和262 MPa,而延伸率和断面收缩率随Nd加入量增大而降低,其值分别从24.7%和39.9%降低到12%和16.7%。Nd加入量为2.6%时,挤压合金具有较好的综合性能。
Abstract
Effects of Nd on microstructure and mechanical properties of extruded Mg-5.0Y-xNd-0.6Zr(x=0,1.0,2.6,4.2,mass fraction/%,the same below) alloy were investigated by optical microscopy(OM),scanning electron microscopy(SEM),X-ray diffraction(XRD) and tensile testing.The results showed that with addition of Nd,the banding particles of β and Mg24Y5 phase in the extruded alloy increased,which promoted the nucleation of dynamic recrystallization,the volume fraction of recrystallization advanced,and the average grain size of recrystallization could be refined from 4.5μm to 2.6μm.The tensile strength and yield strength of extruded alloy increased with increment of Nd,the maximum values of them were 303MPa and 262MPa respectively.The elongation and section shrinkage conspicuous decreased from 24.7% and 39.9% to 12% and 16.7% with increasing Nd content.The extruded alloy displayed better strength and plasticity at Nd content of 2.6%.
关键词
Mg-Y-Nd-Zr合金 /
热挤压 /
动态再结晶 /
力学性能
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Key words
Mg-Y-Nd-Zr alloy /
hot extrusion /
dynamic recrystallization /
mechanical property
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中图分类号：
TG146.2
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参考文献
[1] MORDIKE B L,EBERT T.Magnesium properties-application-potential[J].Materials Science and Engineering A,2001,302(1):37-45.
[2] KOJIMA Y.Platform science and technology for advanced magnesium alloy[J].Materials Science Forum,2000,350-351:3-18.
[3] MOHRI T,MABUCHI M,SAITO N,et al.Microstructure and mechanical properties of a Mg-4Y-3RE alloy processed by thermo-mechanical treatment[J].Materials Science and Engineering A,1998,257(2):287-294.
[4] WANG J G,HSIUNG L M,NIEH T G,et al.Creep of a heat treated Mg-4Y-3RE alloy[J].Materials Science and Engineering A,2001,315(1-2):81-88.
[5] WATANABE H,MUKAI T,ISHIKAWA K,et al.Superplasticity of a particle-strengthened WE 43 magnesium alloy[J].Materials Transactions,2001,42(1):157-162.
[6] LIU X B,CHEN R S,HAN E H.High temperature deformations of Mg-Y-Nd alloys fabricated by different routes[J].Materials Science and Engineering A,2008,497(1-2):326-332.
[7] 唐伟能,陈荣石,韩恩厚.Mg-Y-Nd-Zr合金的高温变形行为与热加工性能[J].金属学报,2006,42(10):1096-1100.
[8] RZYCHO N T,KIE(L)BUS A.Microstructure of WE43 casting magnesium alloys[J].Journal of Achievements in Materials and Manufacturing Engineering,2007,21(1):31-34.
[9] MENG F G,WANG J,LIU H S,et al.Experimental investigation and thermodynamic calculation of phase relations in the Mg-Nd-Y ternary system[J].Materials Science and Engineering A,2007,454-455:266-273.
[10] 陈振华.变形镁合金[M].北京:化学工业出版社,2005.
[11] AL-SAMMAN T,GOTTSTEIN G.Dynamic recrystallization during high temperature deformation of magnesium[J].Materials Science and Engineering A,2008,490(1-2):411-420.
[12] ION S E,HUMPHREYS F J,WHITE S H.Dynamic recrystallisation and the development of microstructure during the high temperature deformation of magnesium[J].Acta Metall,1982,30(10):1909-1919.
[13] LUSSANA D,MASSAZZA M,RIONTINO G.A DSC study of precipitation hardening in a WE43 Mg alloy[J].Journal of Thermal Analysis and Calorimetry,2008,92 (1):223-225.
[14] GALIYEV A,KAIBYSHEV R,GOTTSTEIN G.Correlation of plastic deformation and dynamic recrystallization in magnesium alloy ZK60[J].Acta Mater,2001,49(7):1199-1207.
[15] 张津,章宗和.镁合金及应用[M].北京:化学工业出版社,2004.
[16] ZHANG M,ZHANG W Z.Interpretation of the orientation relationship and habit plane orientation of the equilibrium β-phase in an Mg-Y-Nd alloy[J].Scripta Materialia,2008,59(7):706-709.
[17] 潘金生,仝健民,田明波.材料科学基础[M].北京:清华大学出版社,1998.
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脚注
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基金
国家自然科学基金资助项目(30670562)
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