锻压技术

T5热处理对Mg-Gd-Y-Zr合金筒形件拉压不对称性的影响

英文标题：nfluence of T5 heat treatment on tension-compression asymmetry for Mg-Gd-Y-Zr-Ag alloy cylindrical parts

关键词：热处理拉压不对称性 Mg-Gd-Y-Zr合金力学性能 β′析出相时效处理

分类号：TG146.2

出版年,卷(期):页码：2022,47(12):193-199

摘要：

通过力学性能测试、背散射电子衍射、X射线衍射、透射电子表征等手段分析大尺寸Mg-9.17Gd-1.98Y-0.43Zr-0.11Ag镁合金筒形件的组织性能不均匀性和拉压不对称性，并通过时效处理调控合金组织，提高材料力学性能。研究发现：从内部到外部，筒形件组织呈不均匀分布，平均晶粒尺寸从12.9 μm粗化至20.1 μm，抗拉强度从327 MPa降至280 MPa，屈服强度从223 MPa 降至157 MPa。经225 ℃×21 h峰时效处理后，β′相作为主要析出相，抑制了压缩载荷下孪晶的产生，大幅提高了筒形件的强度并降低其伸长率，压缩屈服强度和拉伸屈服强度的比值从内部到外部分别为1.06、1.17和1.02。T5热处理后筒形件内部的力学性能最好，抗拉强度、屈服强度和伸长率分别为407 MPa、293 MPa和12%。

The inhomogeneity of microstructure and the properties and the tension-compression asymmetry for large-sized Mg-9.17Gd-1.98Y-0.43Zr-0.11Ag magnesium alloy cylindrical part were analyzed by mechanical property testing, backscattered electron diffraction, X-ray diffraction and transmission electron characterization, and the mechanical properties of material were improved by aging treatment to regulate the alloy microstructure. The results show that from the inside to the outside, the microstructure of cylinder part is unevenly distributed, the average grain size is coarsened from 12.9 μm to 20.1 μm, the tensile strength is reduced from 327 MPa to 280 MPa, and the yield strength is reduced from 223 MPa to 157 MPa. After peak aging at 225 °C×21 h, as the main precipitation phase, β′ phase inhibits the generation of twins under compression load, greatly increases the strength of cylinder part and reduces its elongation, and the ratio of compressive yield strength to tensile yield strength is 1.06, 1.17 and 1.02 from the inside to the outside, respectively. After T5 heat treatment, the internal mechanical properties of cylindrical part are the best with the tensile strength of 407 MPa, the yield strength of 293 MPa and the elongation of 12%.

基金项目：

国家自然科学基金资助项目（51574291,51874367）

李梦媛（1997-），女，硕士研究生 E-mail：1015704955@qq.com 通信作者：刘楚明（1960-），男，博士，教授 E-mail：cmliu@csu.edu.cn

参考文献：

[1]李永军，张奎，李兴刚，等.挤压变形对Mg-5.0Y-7.0Gd-1.3Nd-0.5Zr合金组织和性能的影响[J].中国有色金属学报，2010,20(9):1692-1697.

Li Y J,Zang K,Li X G,et al. Influence of extrusion on microstructures and mechanical properties of Mg-5.0Y-7.0Gd-1.3Nd-0.5Zr magnesium alloy[J]. The Chinese Journal of Nonferrous Metals,2010,20(9):1692-1697.

[2]唐列冲. 两向锻造对Mg-10Gd-4.8Y-0.6Zr合金显微组织及力学性能的影响[D].长沙：中南大学，2013.

Tang L C.Microstructures and tensile properties of Mg-10Gd-4.8Y-0.6Zr alloy during two-direction forging[D].Changsha: Central South University,2013.

[3]王必正，高永浩，刘楚明.多向锻造及时效对Mg-Gd-Y-Zr组织和力学性能的影响[J].兵器材料科学与工程，2018,41(4):27-31.

Wang B Z,Gao Y H,Liu C M.Effect of multidirectional forging and ageing treatment on microstructure and mechanical properties of Mg-Gd-Y-Zr alloy[J].Ordnance Material Science and Engineering,2018,41(4):27-31.

[4]骆俊廷，赵静启，李建，等.细晶高强度Mg-Gd-Y-Zn-Zr合金热变形本构方程及组织演变模型[J].中国有色金属学报，2021,31(5):1214-1226.

Luo J T,Zhao J Q,Li J,et al.Constitutive equation and microstructure evolution model of fine-grained and high-strength Mg-Gd-Y-Zn-Zr alloy during hot deformation[J].The Chinese Journal of Nonferrous Metals,2021,31(5):1214-1226.

[5]代晓军，杨西荣，荆磊，等.等通道挤压变形技术制备超细晶镁合金的研究进展[J].稀有金属,2020,44(12):1325-1332.

Dai X J，Yang X R，Jing L，et al. Research progress in ultrafine grain magnesium alloy by equal channel angular pressing[J]. Chinese Journal of Rare Metals. 2020,44(12):1325-1332.

[6]闫勇，张星，李保成.不同挤压态组织对Mg-13Gd-4Y-2Zn-0.5Zr合金时效行为的影响[J].热加工工艺，2019,48(6):232-235.

Yan Y,Zhang X,Li B C. Effect of different extruded microstructure on aging behavior of Mg-13Gd-4Y-2Zn-0.5Zr Alloy[J].Hot Working Technology,2019,48(6):232-235.

[7]沈光明，顾洪兵，刘东军，等.锻造及热处理对Mg-8.5Gd-3.2Y-0.4Zr合金显微组织及力学性能的影响[J].热加工工艺，2016,45(21):148-150.

Shen G M,Gu H B,Liu D J,et al.Effect of forging and heat treatment on microstructure and mechanical properties of Mg-8.5Gd-3.2Y-0.4Zr alloy[J].Hot Working Technology,2016,45(21):148-150.

[8]Zheng J X,Li Z,Tan L D,et al.Precipitation in Mg-Gd-Y-Zr alloy: Atomic-scale insights into structures and transformations[J].Materials Characterization,2016,117:76-83.

[9]Liu H,Gao Y,Liu J Z,et al.A simulation study of the shape of β′ precipitates in Mg-Y and Mg-Gd alloys[J].Acta Materialia,2013,61(2)：453-466.

[10]Homma T,Kunito N,Kamado S.Fabrication of extraordinary high-strength magnesium alloy by hot extrusion[J].Scripta Materialia,2009,61(6):644-647.

[11]Xu C,Zheng M Y,Xu S W.Ultra high-strength Mg-Gd-Y-Zn-Zr alloy sheets processed by large-strain hot rolling and ageing[J].Materials Science and Engineering A,2012,547:93-98.

[12]Zhang D D,Liu C M,Wan Y C,et al.Microstructure and anisotropy of mechanical properties in ring rolled AZ80-Ag alloy[J].Journal of Central South University,2021,28(5):1316-1323.

[13]Zeng G,Liu C M,Gao Y H,et al.Microstructure and mechanical properties of AZ80-Ag alloy processed by hot ring rolling[J].Materials Science and Engineering A,2016,674:491-497.

[14]Yu S L,Liu C M,Gao Y H,et al.Microstructure, texture and mechanical properties of Mg-Gd-Y-Zr alloy annular forging processed by hot ring rolling[J].Materials Science and Engineering A,2017,689:40-47.

[15]张宗良，刘楚明，高永浩，等.Mg-9Gd-3Y-0.6Zr-0.05Ag镁合金模锻件微观组织及力学性能不均匀性研究[J].锻压技术，2021,46(2):206-212.

Zhang Z L,Liu C M, Gao Y H,et al.Study on inhomogeneity of microstructure and mechanical property for Mg-9Gd-3Y-0.6Zr-0.05Ag magnesium alloy die forgings[J].Forging & Stamping Technology,2021,46(2):206-212.

[16]Valle J,Carreno F,Ruano O A J.Influence of texture and grain size on work hardening and ductility in magnesium-based alloys processed by ECAP and rolling[J].Acta Materialia,2007,54(16):4247-4259.

[17]Marko K,Amanda L,Ryan H,et al.Deformation twinning in AZ31:Influence on strain hardening and texture evolution[J].Acta Materialia,2010,58(19):6230-6242.

[18]Zhang Y,Rong W,Wu Y J,et al.A comparative study of the role of Ag in microstructures and mechanical properties of Mg-Gd and Mg-Y alloys[J].Materials Science and Engineering A,2018,731:609-622.

[19]Bhattacharyya J J,Wang F, Mcquade P J,et al.Deformation and fracture behavior of Mg alloy, WE43, after various aging heat treatments[J].Materials Science and Engineering A,2017,705:79-88.

[20]Yu Z J,Xu C,Meng J,et al.Microstructure evolution and mechanical properties of a high strength Mg-11.7Gd-4.9Y-0.3Zr (wt%) alloy prepared by pre-deformation annealing,hot extrusion and ageing[J].Materials Science and Engineering A,2017,703:348-358.

[21]Robson J D,Stanford N,Barnett M R.Effect of precipitate shape on slip and twinning in magnesium alloys[J].Acta Materialia,2011,59(5):1945-1956.

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