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21 4 2011 4 Vol.21 No.4 The Chinese Journal of Nonferrous Metals Apr. 2011 1004-0609(2011)04-0708-06 Al-4.74Cu-0.50Mg-0.30Ag X 1 1 1 1 2 1 3 (1., 100088 2. 100088 3. 201204) X (SAXS) (TEM) Al-4.74Cu-0.50Mg-0.30Ag Ω θ TG 146.2 A Small angle X-ray scattering study of Al-4.74Cu-0.50Mg-0.30Ag alloys during aging process ZHANG Jian-bo 1, ZHANG Yong-an 1, ZHU Bao-hong 1, WANG Feng 1, ZHENG Yi 2, XIONG Bai-qing 1, WANG Yu-zhu 3 (1. State Key Laboratory for Fabrication and Processing of Nonferrous Metals, General Research Institute for Nonferrous Metals, Beijing 100088, China; 2. Department of Powder Metallurgy, Central Iron and Steel Research Institute, Beijing 100081, China; 3. Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China) Abstract: The precipitation behavior of Al-4.74Cu-0.50Mg-0.30Ag alloys during single aging process was studied by the synchrotron-radiation small angle X-ray scattering (SAXS), transmission electron microscopy analysis (TEM) and mechanical property test. The results show that the Ω phase and little θ phases precipitate during single aging process, and with prolonging the aging time, the radial size of the precipitates increases notably, whereas the width of the precipitates increases little, therefore, the shape of the precipitates gradually changes into thin plates. The size of the precipitation increases at the beginning of aging process and goes to a stable value at last. The volume fraction of the precipitation increases at the beginning and then decreases, at last increases in a smaller rate. Key words: aluminum alloys; small angle X-ray scattering; precipitation; volume fraction Al-Cu-Mg-Ag, [1] Cu/Mg Al-Cu-Mg GP ( {100} ) θ θ θ Ag Al-Cu-Mg (150 ) Ag Al-Cu-Mg-Ag GPB ( {111} (50904010) 2010-04-16 2010-07-29 010-82241165 E-mail: zhang4318@163.com

21 4 Al-4.74Cu-0.50Mg-0.30Ag X 709 ) Ω θ θ Ω [1 2] (TEM) (HREM) Ω [2 6] HONO [7] TEM X RINGER [8] TEM Ω θ Ω 200 SONG [9] TEM / LIU [10] TEM TEM X X Al-Li Al-Zn-Mg-Cu Al-Li-Mg-Cu Al-Mg-Si [10 14] Al-Cu-Mg-Ag X SAXS Al-4.74Cu-0.50Mg-0.30Ag ( ) Al-Cu-Mg-Ag X 30% + 70% ( ) 16~18 V 70~90 ma 30~ 20 JEM 2000FX TEM 1.3 X X (Small angle X-ray scattering, SAXS) X ρ ρ 0 (ρ ρ 0 ) 2 X X X 25 mm 25 mm 0.13 mm 5~20 kev 10 kev 6 10 4 1 10 11 S 1 0.5 mm 0.5 mm λ 0.124 nm 4 10 4 rad(0.023º) 2 2.1 1 Al-Cu-Mg-Ag 160 180 1 1.1 ( ) Cu 4.74% Mg 0.50% Ag 0.30% Al 12.3 520 2 h 160 170 180 200 1.2 GB/T16865 97 TEM 1 Al-Cu-Mg-Ag 160 180 Fig.1 Yield strength aging time curves of Al-Cu-Mg-Ag alloy at 160 and 180 during single aging

710 2011 4 160 10 h 180 4 h 450 MPa 180 160 2.2 160 180 Al-Cu-Mg-Ag 2 110 α 2(b) (d) (f)tem (1/3) {022} (2/3) {022} 110 α Ω (1/2){022} 001 θ 2(a) (c) (e) TEM Ω θ (2~10 h) (10~28 h) 2 Al-Cu-Mg-Ag Fig.2 TEM bright field images ((a), (c), (e)) and corresponding selected area electron diffraction patterns ((b), (d), (f)) of Al-Cu-Mg-Ag alloy during single aging process: (a) T6 temper; (a), (b) 160, 2 h; (c), (d) 160, 10 h; (e), (f) 160, 28 h

21 4 Al-4.74Cu-0.50Mg-0.30Ag X 711 2.3 X 2.3.1 X 3 [15] FIT2D 0~360 SAXS 4 (160, 20 min) (160, 8 h) Guinier I(h) h h=4πsinθ/λ 2θ λ 2.3.2 Guinier [16] e 2 2 2 G Ih ( ) = INn exp( Rh /3) (1) I(h) I e n N X R G 3 (a) Guinier ln I(h) h 2 ( 4(b)), Guinier α, R = α (2) G 3 R 3 X Fig.3 SAXS results of alloys after different heat-treatments: (a) 180, 20 min; (b) 180, 1 h; (c) 180, 4 h; (d) 180, 40 h

712 2011 4 4 Guinier Fig.4 Scattering and Guinier curves under different aging conditions: (a) I(h) vs h; (b) ln I(h) vs h 2 5 Fig.5 Relationship between gyration radius and aging temperature and time R R G = (3) 2 4(b) 5 5 Al-Cu-Mg-Ag Ω [17] 2.3.3 0 2 2 2π 2 2 2 2 p m ϕ ϕ Vat Qh = I( h) h d h= ( Z) ( c c ) (1 ) (4) I(h) V at Al ( 16.6 Å 3 ) Z Al c p c m ϕ ( ), 6 ϕ 0.5, ϕ( 1 ϕ), ϕ [11] 0.5 6

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