新型Al-Mg-Sc-Zr合金显微组织和性能研究
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摘要
采用半连续铸造方法制备了一种新型的Al-5.5Mg-0.078Sc-0.15Zr (%,质量分数)合金铸锭,通过性能测试和电子显微分析技术研究了该合金板材制备过程中的组织性能演变规律。结果表明:铸态合金主要由富含(Fe, Mn)杂质相和Mg_2Al_3相构成。均匀化处理过程中,可溶性金属间化合物Mg_2Al_3先析出,后逐步溶入基体中,优化的均匀化工艺为350℃×10 h+440℃×6 h。随稳定化退火温度的升高,合金的强度降低,延伸率升高,剥落腐蚀敏感性降低,腐蚀电流密度降低。Al-Mg-Sc-Zr合金板材经过330℃退火1 h后可获得最优综合性能,其中σ_b,σ_(0.2)与δ分别为424, 348 MPa和13.1%,剥落腐蚀等级为PA。研究合金具有高合金强度主要源于Al_3(Sc,Zr)粒子产生的奥罗万强化和亚结构强化作用;随稳定化温度的升高,合金内的Mg_2Al_3相在高温稳定化退火中发生了一定回溶,因此剥落腐蚀抗力提高。
A new type of Al-5.5 Mg-0.078 Sc-0.15 Zr(%, mass fraction) alloy ingot was designed by semi-continuous casting method. The microstructure and properties of the alloy sheet were studied by means of properties test and electron microscopic analysis technology. The results showed that the as-cast alloy was mainly composed of(Fe,Mn) impurity phase and Mg_2Al_3 phase. In the homogenization process, the soluble metallic compound Mg_2Al_3 precipitated first, then gradually dissolved into the matrix, and the optimized homogenization process was 350 ℃×10 h+440 ℃×6 h. With the stabilizing annealing temperature increasing, the strength of the alloy decreased, the elongation increased, the susceptibility to exfoliation corrosion decreased, and the corrosion current density decreased. The optimized comprehensive properties of Al-Mg-Sc-Zr alloy sheet after annealing at 330 ℃ for 1 h were obtained, in which the σ_b, σ_(0.2) and δ were 424, 348 MPa and 13.1%, respectively, and the exfoliation corrosion grade was PA. The studied alloy with high alloy strength was mainly caused by Orowan strengthening and substructure strengthening effect of Al_3(Sc,Zr) particles. With the increase of the stabilizing temperature, the Mg_2Al_3 phase in the alloy came back tomatrix during the high temperature stabilizing annealing, so the resistance to exfoliation corrosion increased.
A new type of Al-5.5 Mg-0.078 Sc-0.15 Zr(%, mass fraction) alloy ingot was designed by semi-continuous casting method. The microstructure and properties of the alloy sheet were studied by means of properties test and electron microscopic analysis technology. The results showed that the as-cast alloy was mainly composed of(Fe,Mn) impurity phase and Mg_2Al_3 phase. In the homogenization process, the soluble metallic compound Mg_2Al_3 precipitated first, then gradually dissolved into the matrix, and the optimized homogenization process was 350 ℃×10 h+440 ℃×6 h. With the stabilizing annealing temperature increasing, the strength of the alloy decreased, the elongation increased, the susceptibility to exfoliation corrosion decreased, and the corrosion current density decreased. The optimized comprehensive properties of Al-Mg-Sc-Zr alloy sheet after annealing at 330 ℃ for 1 h were obtained, in which the σ_b, σ_(0.2) and δ were 424, 348 MPa and 13.1%, respectively, and the exfoliation corrosion grade was PA. The studied alloy with high alloy strength was mainly caused by Orowan strengthening and substructure strengthening effect of Al_3(Sc,Zr) particles. With the increase of the stabilizing temperature, the Mg_2Al_3 phase in the alloy came back tomatrix during the high temperature stabilizing annealing, so the resistance to exfoliation corrosion increased.
引文
[1] Zha M,Li Y,Mathiesen R H,Bj?rge R,Roven H J.Microstructure evolution and mechanical behavior of a binary Al-7Mg alloy processed by equal-channel angular pressing [J].Acta Materialia,2015,84:42.
[2] Tuan N Q,Alves A C,Toptan F,Lopes A B,Pinto A M P.Effects of substituting ytterbium for scandium on corrosion behaviour of Al-Sc alloy [J].Materials and Corrosion,2016,66(12):1504.
[3] Zhang X W,Hu H T,Zhu C L,Li S,Zhang J.Deformation behavior during creep of lamellar TiAl alloys at relatively high stress with minor C alloying addition [J].Chinese Journal of Rare Metals,2017,41(9):972.(张熹雯,胡海涛,朱春雷,李胜,张继.微量C对层片组织TiAl合金高应力蠕变变形的影响 [J].稀有金属,2017,41(9):972.)
[4] Pan Q L,Yin Z M,Zou J X,Chen X M,Zhang C F.The role of trace Sc in Al-Mg alloys [J].Acta Metallurgica Sinica,2001,37(7):749.(潘青林,尹志民,邹景霞,陈显明,张传福.微量Sc在Al-Mg合金中的作用 [J].金属学报,2001,37(7):749.)
[5] Marquis E A,Seidman D N.Coarsening kinetics of nanoscale Al3Sc precipitates in an Al-Mg-Sc alloy [J].Acta Materialia,2005,53(15):4259.
[6] Seidman D N,Marquis E A,Dunand D C.Precipitation strengthening at ambient and elevated temperatures of heat-treatable Al(Sc) alloys [J].Acta Materialia,2002,50(16):4021.
[7] Harada Y,Dunand D C.Microstructure of Al3Sc with ternary transition-metal additions [J].Materials Science and Engineering A,2016,329(249):686.
[8] Deng Y,Yin Z,Zhao K,Duan J,He Z.Effects of Sc and Zr microalloying additions on the microstructure and mechanical properties of new Al-Zn-Mg alloys [J].Journal of Alloys and Compounds,2012,530(7):71.
[9] Tolley A,Radmilovic V,Dahmen U.Segregation in Al3(Sc,Zr) precipitates in Al-Sc-Zr alloys [J].Scripta Materialia,2005,52(7):621.
[10] Forbord B,Lefebvre W,Danoix F,Hallem H,Marthinsen K.Three dimensional atom probe investigation on the formation of Al(Sc,Zr)-dispersoids in aluminium alloys [J].Scripta Materialia,2004,51(4):333.
[11] Clouet E,Laé L,Epicier T,Lefebvre W,Nastar M,Deschamps A.Complex precipitation pathways in multicomponent alloys.[J].Nature Materials,2006,5(6):482.
[12] Vlach M,Stulíkov á I,Smola B,Vlach M,Stulíkov á I,Smola B,?aludov .Phase transformations in isochronally annealed mould-cast and cold-rolled Al-Sc-Zr-based alloy [J].Journal of Alloys and Compounds,2010,492(1):143.
[13] Deng Y,Yin Z,Zhao K,Duan J,He Z.Effects of Sc and Zr microalloying additions on the microstructure and mechanical properties of new Al-Zn-Mg alloys [J].Journal of Alloys and Compounds,2012,530(7):71.
[14] Peng Y Y,Li S,Deng Y,Zhou H,Xu G F,Yin Z M.Synergetic effects of Sc and Zr microalloying and heat treatment on mechanical properties and exfoliation corrosion behavior of Al-Mg-Mn alloys [J].Materials Science and Engineering A,2016,666:61.
[15] Zhou H,Wang Y E.Effect of annealing temperature on the exfoliation corrosion properties of Al-7.0Mg alloy [J].Aluminum Processing,2001,24 (5):32.(周华,王悦娥.退火温度对Al-7.0Mg合金剥落腐蚀性能的影响 [J].铝加工,2001,24(5):32.)
[16] Li C.Principles of Metallography [M].Harbin:Harbin Institute of Technology Press,1989.321.(李超.金属学原理 [M].哈尔滨:哈尔滨工业大学出版社,1989.321.)
[17] Ocenasek V,Slamova M.Resistance to recrystallization due to Sc and Zr addition to Al-Mg alloys [J].Materials Characterization,2001,47(2):157.
[18] Zhang Y H,Yin Z M.Effects of Sc and Zr addition on microstructure and mechanical properties of Al-Mg Alloys [J].Chinese Journal of Rare Earths,2002,(3):29.(张永红,尹志民.微量Sc,Zr对Al-Mg合金的组织和力学性能的影响 [J].中国稀土学报,2002,(3):29.)
[19] Ryset J,Ryum N.Scandium in aluminum alloys [J].International Materials Reviews,2005,50(1):19.
[20] Wu L M,Seyring M,Rettenmayr M,Wang W H.Characterization of precipitate evolution in an artificially aged Al-Zn-Mg-Sc-Zr alloy [J].Materials Science and Engineering A,2010,527(4-5):1068.
[21] Yasakau K A,Zheludkevich M L,Lamaka S V,Ferreira M G S.Role of intermetallic phases in localized corrosion of AA5083 [J].Electrochimica Acta,2007,52(27):7651.
[22] Goswami R,Spanos G,Pao P S,Holtz R L.Microstructural evolution and stress corrosion cracking behavior of Al-5083 [J].Metallurgical and Materials Transactions A,2011,42(2):348.
[2] Tuan N Q,Alves A C,Toptan F,Lopes A B,Pinto A M P.Effects of substituting ytterbium for scandium on corrosion behaviour of Al-Sc alloy [J].Materials and Corrosion,2016,66(12):1504.
[3] Zhang X W,Hu H T,Zhu C L,Li S,Zhang J.Deformation behavior during creep of lamellar TiAl alloys at relatively high stress with minor C alloying addition [J].Chinese Journal of Rare Metals,2017,41(9):972.(张熹雯,胡海涛,朱春雷,李胜,张继.微量C对层片组织TiAl合金高应力蠕变变形的影响 [J].稀有金属,2017,41(9):972.)
[4] Pan Q L,Yin Z M,Zou J X,Chen X M,Zhang C F.The role of trace Sc in Al-Mg alloys [J].Acta Metallurgica Sinica,2001,37(7):749.(潘青林,尹志民,邹景霞,陈显明,张传福.微量Sc在Al-Mg合金中的作用 [J].金属学报,2001,37(7):749.)
[5] Marquis E A,Seidman D N.Coarsening kinetics of nanoscale Al3Sc precipitates in an Al-Mg-Sc alloy [J].Acta Materialia,2005,53(15):4259.
[6] Seidman D N,Marquis E A,Dunand D C.Precipitation strengthening at ambient and elevated temperatures of heat-treatable Al(Sc) alloys [J].Acta Materialia,2002,50(16):4021.
[7] Harada Y,Dunand D C.Microstructure of Al3Sc with ternary transition-metal additions [J].Materials Science and Engineering A,2016,329(249):686.
[8] Deng Y,Yin Z,Zhao K,Duan J,He Z.Effects of Sc and Zr microalloying additions on the microstructure and mechanical properties of new Al-Zn-Mg alloys [J].Journal of Alloys and Compounds,2012,530(7):71.
[9] Tolley A,Radmilovic V,Dahmen U.Segregation in Al3(Sc,Zr) precipitates in Al-Sc-Zr alloys [J].Scripta Materialia,2005,52(7):621.
[10] Forbord B,Lefebvre W,Danoix F,Hallem H,Marthinsen K.Three dimensional atom probe investigation on the formation of Al(Sc,Zr)-dispersoids in aluminium alloys [J].Scripta Materialia,2004,51(4):333.
[11] Clouet E,Laé L,Epicier T,Lefebvre W,Nastar M,Deschamps A.Complex precipitation pathways in multicomponent alloys.[J].Nature Materials,2006,5(6):482.
[12] Vlach M,Stulíkov á I,Smola B,Vlach M,Stulíkov á I,Smola B,?aludov .Phase transformations in isochronally annealed mould-cast and cold-rolled Al-Sc-Zr-based alloy [J].Journal of Alloys and Compounds,2010,492(1):143.
[13] Deng Y,Yin Z,Zhao K,Duan J,He Z.Effects of Sc and Zr microalloying additions on the microstructure and mechanical properties of new Al-Zn-Mg alloys [J].Journal of Alloys and Compounds,2012,530(7):71.
[14] Peng Y Y,Li S,Deng Y,Zhou H,Xu G F,Yin Z M.Synergetic effects of Sc and Zr microalloying and heat treatment on mechanical properties and exfoliation corrosion behavior of Al-Mg-Mn alloys [J].Materials Science and Engineering A,2016,666:61.
[15] Zhou H,Wang Y E.Effect of annealing temperature on the exfoliation corrosion properties of Al-7.0Mg alloy [J].Aluminum Processing,2001,24 (5):32.(周华,王悦娥.退火温度对Al-7.0Mg合金剥落腐蚀性能的影响 [J].铝加工,2001,24(5):32.)
[16] Li C.Principles of Metallography [M].Harbin:Harbin Institute of Technology Press,1989.321.(李超.金属学原理 [M].哈尔滨:哈尔滨工业大学出版社,1989.321.)
[17] Ocenasek V,Slamova M.Resistance to recrystallization due to Sc and Zr addition to Al-Mg alloys [J].Materials Characterization,2001,47(2):157.
[18] Zhang Y H,Yin Z M.Effects of Sc and Zr addition on microstructure and mechanical properties of Al-Mg Alloys [J].Chinese Journal of Rare Earths,2002,(3):29.(张永红,尹志民.微量Sc,Zr对Al-Mg合金的组织和力学性能的影响 [J].中国稀土学报,2002,(3):29.)
[19] Ryset J,Ryum N.Scandium in aluminum alloys [J].International Materials Reviews,2005,50(1):19.
[20] Wu L M,Seyring M,Rettenmayr M,Wang W H.Characterization of precipitate evolution in an artificially aged Al-Zn-Mg-Sc-Zr alloy [J].Materials Science and Engineering A,2010,527(4-5):1068.
[21] Yasakau K A,Zheludkevich M L,Lamaka S V,Ferreira M G S.Role of intermetallic phases in localized corrosion of AA5083 [J].Electrochimica Acta,2007,52(27):7651.
[22] Goswami R,Spanos G,Pao P S,Holtz R L.Microstructural evolution and stress corrosion cracking behavior of Al-5083 [J].Metallurgical and Materials Transactions A,2011,42(2):348.