Au-Ag-Al系相图的热力学优化和计算  

Thermodynamic optimization and calculation of the phase diagrams of Au-Ag-Al system

作　　者：邓力川 王效琪[1] 周晓龙[1] 于杰[1] 刘满门[2] 王立惠 DENG Lichuan;WANG Xiaoqi;ZHOU Xiaolong;YU Jie;LIU Manmen;WANG Lihui(School of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China;Kunming Institute of Precious Metals,Kunming 650106,China;Guilin Key Laboratory of Microelectronic Electrode Materials and Biological Nanomaterials,China Nonferrous Metal(Guilin)Geology and Mining Co.Ltd.,Guilin 541004,Guangxi,China)

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093 [2]昆明贵金属研究所,昆明650106 [3]中国有色桂林矿产地质研究院有限公司桂林市微电子元件电极材料与生物纳米材料重点实验室,广西桂林541004

出　　处：《贵金属》2024年第2期11-18,共8页Precious Metals

基　　金：云南省重大科技计划(202102AB080008-1)。

摘　　要：使用计算相图方法(CALPHAD)计算Au-Ag-Al的三元相图时,三个边际二元相图(Au-Al,Au-Ag,Ag-Al)的准确性对三元相图的计算有很大的影响,目前Au-Al边际二元相图存在着一定的矛盾。在综合评估Au-Al体系实验数据的基础上,优化和计算了Au-Al合金体系的平衡相图,使用置换式溶体溶液模型描述Au-Al体系中液相、Bcc和Fcc相的吉布斯自由能,分别用亚点阵模型(Al)(Au)_(4)、(Al)_(3)(Au)_(8)、(Al)(Au)_(2)、(Al)(Au)和(Al,Au)_(2)(Al,Au)描述AlAu_(4)、Al_(3)Au_(8)、AlAu_(2)、AlAu和Al_(2)Au相,通过Pandat软件优化得到一组各相的热力学参数,计算得到的Au-Al相图与实验数据和热力学数据相吻合。结合Au-Ag和Ag-Al的热力学参数,计算了Au-Ag-Al液相面投影图和等温截面图,液相面投影图显示该三元系存在8个四相平衡反应,对Au-Ag-Al合金的研究具有指导意义。When the calculation of phase diagram(CALPHAD)method is applied to the Au-Ag-Al ternary phase diagram,the accuracy of three marginal binary phase diagrams(Au-Al,Au-Ag,Ag-Al)has a great impact on the calculating results.At present,there are some contraditions in the Au-Al marginal binary phase diagram.Therefore,based on a comprehensive evaluation of experimental data for the Au-Al system,the equilibrium phase diagrams were optimised and calculated by using a solid solution model to describe the Gibbs free energy of the liquid,Bcc and Fcc phases in the Au-Al system,and by using the sublattice models(Al)(Au)4,(Al)_(3)(Au)_(8),(Al)(Au)_(2),(Al)(Au)and(Al,Au)_(2)(Al,Au)to describe the AlAu4,Al3Au8,AlAu2,AlAu and Al2Au phases.A set of reasonably self-consistent thermodynamic parameters was obtained via optimizing with Pandat software.Au-Al phase diagrams calculated in this way agreed well with the experimental and thermodynamic data.Combined with thermodynamic parameters of Au-Ag and Ag-Al,the Au-Ag-Al liquid-phase,surface projections and isothermal cross-sections were calculated.The liquid-phase surface projections revealed the existence of eight four-phase equilibrium reactions in this ternary system,and these results may be helpful in studying the Au-Ag-Al alloys.

关 键 词：Au-Ag-Al 计算相图(CALPHAD) 热力学计算 相图 

分 类 号：TG146.3[一般工业技术—材料科学与工程]