采用合金法,利用X射线衍射、扫描电镜及能谱成分分析等手段测定Mg-Zn-Al合金350℃时的相平衡关系及其成分,建立富镁角350℃等温截面.结果表明:α-Mg固溶体与L、φ、γ三相保持相平衡关系,不存在以前普遍认为的τ与α-Mg 的相平衡.获得350℃时φ相成分范围,即53.5%~57.2%Mg、17.7%~30.7%Zn 和15.8%~27.7%Al(摩尔分数).Zn和Al两种元素可以同时固溶于α-Mg相中.但Al的加入提高了Zn在α-Mg中的溶解度,当α-Mg和L相平衡时,溶解度最大可达3.9%,远大于Mg-Zn二元系的2.1%.而当α-Mg与γ相平衡时,Zn的加入降低Al在α-Mg中的溶解度,即由Mg-Al二元系的7.8%降至5.2%.Al在Mg-Zn二元金属间化合物中的固溶度较大,可达7.7%,从而使其热稳定性得到提高.
@@@@The phase equilibria and their compositions in the Mg-rich corner of Mg-Zn-Al ternary system at 350℃were determined through the equilibrated alloy method by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) assisted with energy dispersive spectroscopy (EDS), and thus the isothermal section of the Mg-rich corner at 350 ℃ in the ternary system was constructed. There are three phases at this temperature in equilibrium withα-Mg solid solution, including the liquid, φ and γ phases, while not the τ ternary intermetallic compound as previously accepted. Moreover, the composition ranges of the φ intermetallic compound, i.e., 53.5%?57.2%Mg, 17.7%?30.7%Zn and 15.8%?27.7%Al (mole fraction), are also obtained. The zinc and aluminum are simultaneously soluble in theα-Mg phase. The solubility of Zn in theα-Mg phase increases due to the addition of Al, and the maximum solubility is 3.0%Zn, more than that of Mg-Zn binary system (2.1%Zn) when the α-Mg solid solution is in equilibrium with the liquid phase. However, the solubility of Al in the α-Mg phase decreases due to the addition of Zn when the α-Mg phase is in equilibrium with theγintermetallic compound, i.e., the Al solubility is 7.8%in the Mg-Al binary system, decreasing to 5.2%. At the same time, the solubility of the Al in the Mg-Zn intermetallic compound is improved to 7.7%.
参考文献
| [1] | Z. ZHANG;R. TREMBLAY .SOLIDIFICATION MICROSTRUCTURE OF ZA102, ZA104 AND ZA106 MAGNESIUM ALLOYS AND ITS EFFECT ON CREEP DEFORMATION[J].Canadian Metallurgical Quarterly,2000(4):503-512. |
| [2] | VOGEL M;KRAFT O;ARZT E .Creep behavior of magnesium die-cast alloy ZA85[J].Scripta Materialia,2003,48(08):985-990. |
| [3] | ZHANG Jing,LI Zhong-sheng,GUO Zheng-xiao,PAN Fu-sheng.Solidification microstructural constituent and its crystallographic morphology of permanent-mould-cast Mg-Zn-Al alloys[J].中国有色金属学会会刊（英文版）,2006(02):452-458. |
| [4] | M. Vogel;O. Kraft;G. Dehm .Quasi-crystalline grain-boundary phase in the magnesium die-cast alloy ZA85[J].Scripta materialia,2001(5):517-524. |
| [5] | Oh-Ishi, K;Hono, K;Shin, KS .Effect of pre-aging and Al addition on age-hardening and microstructure in Mg-6 wt% Zn alloys[J].Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing,2008(1/2):425-433. |
| [6] | 陈建波,黄晓锋.Mg-Zn-Al系镁合金研究现状与发展[J].热加工工艺,2011(22):48-51,54. |
| [7] | 朱蓓蓓,孙扬善,万晓峰,薛烽.Mg-Zn-Al系变形镁合金的显微组织和力学性能[J].东南大学学报（自然科学版）,2010(03):640-645. |
| [8] | 杨明波,潘复生,汤爱涛,唐丽文,杨慧.Mg-Zn-Al（ZA）系耐热镁合金的研究现状[J].热加工工艺,2007(08):73-77. |
| [9] | 赵玮霖,杨明波,潘复生,白亮,唐丽文.合金元素对Mg-Zn-Al（ZA）系耐热镁合金组织及性能的影响[J].材料导报,2007(07):70-73. |
| [10] | Jing Zhang;Z.X. Guo;Fusheng Pan;Zhongsheng Li;Xiaodong Luo .Effect of composition on the microstructure and mechanical properties of Mg-Zn-Al alloys[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2007(1/2):43-51. |
| [11] | ZHANG J;ZUO R L;CHEN Y X;PAN F S LUO X D .Microstructure evolution during homogenization of a τ-type Mg-Zn-Al alloy[J].Journal of Alloys and Compounds,2008,448(1/2):316-320. |
| [12] | 冯凯,黄晓锋,马颖,陈娟娟,郝远.固溶时间对ZA72镁合金显微组织及力学性能的影响[J].中国有色金属学报,2011(09):2035-2042. |
| [13] | REN Y P;QIN G W;PEI W L;GUO Y ZHAO H D LI H X JIANG M HAO S M .Theα-Mg solvus and isothermal section of Mg-rich corner in the Mg-Zn-Al ternary system at 320℃[J].Journal of Alloys and Compounds,2009,481(1/2):176-181. |
| [14] | 任玉平,秦高梧,裴文利,李松,郭运,赵宏达.Mg-Zn-Al三元系富镁角在300℃的相平衡[J].中国有色金属学报（英文版）,2012(02):241-245. |
| [15] | VILLARS P;PRINCE A;OKAMOTO H.Handbook of ternary alloy phase diagrams[M].Materials Park,OH,ASM International,1997 |
| [16] | EFFENBERG G;ILTENKO S.Ternary alloy systems-Phase diagrams,crystallographic and thermodynamic data[M].Germany:Springer,2006:191. |
| [17] | Liang P.;Robinson JA.;Wagner S.;Ochin P.;Harmelin MG. Seifert HJ.;Lukas HL.;Aldinger F.;Tarfa T. .Experimental investigation and thermodynamic calculation of the Al-Mg-Zn system[J].Thermochimica Acta: An International Journal Concerned with the Broader Aspects of Thermochemistry and Its Applications to Chemical Problems,1998(1/2):87-110. |
| [18] | M. Ohno;D. Mirkovic;R. Schmid-Fetzer .Phase equilibria and solidification of Mg-rich Mg-Al-Zn alloys[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2006(1/2):328-337. |
| [19] | OKAMOTO H .Comment on Mg-Zn (magnesium-zinc)[J].Journal of Phase Equilibria,1994,15(01):129-130. |
| [20] | MASSALSKI T B;OKAMOTO H.Binary alloy phase diagrams[M].Materials Park,OH,ASM International,1990:169-171. |
| [21] | Ren, Y.P.;Guo, Y.;Chen, D.;Li, S.;Pei, W.L.;Qin, G.W. .Isothermal section of MgZnZr ternary system at 345 ° C[J].Calphad: Computer Coupling of Phase Diagrams and Thermochemistry,2011(3):411-415. |
| [22] | ZHAO H D;QIN G W;REN Y P;PEI W L GUO Y .Isothermal sections of the Mg-rich corner in the Mg-Sn-Y ternary system at 300 and 400℃[J].Journal of Alloys and Compounds,2009,48(1/2):140-143. |
| [23] | CáCERES C H;ROVERA D M .Solid solution strengthening in concentrated Mg-Al alloys[J].J Light Met,2001,1(03):151-156. |
| [24] | Caceres CH.;Blake A. .The strength of concentrated Mg-Zn solid solutions[J].Physica Status Solidi, A. Applied Research,2002(1):147-158. |
| [25] | Buha J .Reduced temperature (22-100 degrees C) ageing of an Mg-Zn alloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008(1/2):11-19. |
| [26] | Rosalie, J.M.;Somekawa, H.;Singh, A.;Mukai, T..The effect of size and distribution of rod-shaped β1' precipitates on the strength and ductility of a Mg-Zn alloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2012:230-237. |
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