相图计算研究的进展

相图计算作为材料设计的一部分受到了人门更多的重视.本文概述了相图计算的优点,简要评述了相图计算方法的发展现状和前沿研究,着重强调了将第一性原理计算和相图计算方法相结合以及基于相图计算热力学数据库预测体系物理性质对于材料设计和冶金过程优化的重要性.     

第一性原理计算在相图计算中的应用研究进展

相图计算 （Calculation of Phase Diagram, CALPHAD)是冶金 、化工 、材料设计等各个领域的重要研究工具,随着传统材料体系的研究深入和新材料体系的不断被发现,相关的相图和热力学实验数据愈显匮乏.基于电子层面的第一性原理计算（First-principles Calculations),可以从体系基态性质出发,研究亚稳相、金属间化合物的结构、合金的稳定性,促进 CALPHAD 的发展.文中关注了近年来第一性原理计算在 CALPHAD 技术当中的应用研究进展,从计算化合物的能量性质,相图,动力学性质等方面进行系统阐述.      

相图计算及其应用

综述相图计算方法的发展现状、相图热力学计算常用的相描述模型及常用的热力学计算软件,并以Cu–Fe–Mn和Fe–Mn–Ni体系为例重点介绍相图热力学计算在材料设计及制备中的应用。     

镁的合金化与合金相图

论文分析了镁基合金二元和多元相图的研究现状；指出了镁合金在合金化中存在的问题。在此基础上探讨了在镁合金的设计与研究过程中如何进行相图的研究。指出由6－10个元素组成镁合金集团进行合金相图的实验测定和热力学计算的方案是可行的。     

基于Thermo--Calc的中锰中铝Fe--Mn--Al--C低密度钢类Schaeffler相图绘制与评估

含铝低密度钢由于其较好的综合力学性能和低密度特征引起结构钢领域研究人员的广泛关注.本文利用ThermoCalc热力学计算软件结合TCFE 7数据库,计算中锰中铝含量Fe-Mn-Al-C钢在不同温度的热力学平衡状态,总结其两相区相比例的变化规律,通过平移和修正等处理方法,绘制针对中锰中铝钢合金成分和相设计的类Schaeffler相图.结合马氏体转变温度的计算讨论对应不同合金成分条件下相种类存在可能,并通过已有材料的相比例和相形貌实验结果分析绘制的类Schaeffler相图的准确性和适用性.绘制的Fe-Mn-Al-C类Schaeffler相图可以直观地提供不同合金成分所对应的相比例、相种类等信息,可用于新型含铝低密度钢的合金设计.      

有色金属合金体系气液相平衡研究进展

真空蒸馏是从液相到气相的传质过程,合金的气液相平衡相图是真空蒸馏设计的重要理论依据,根据气液相平衡相图可以预判蒸馏最终产物以及分离提纯效果,因此准确的气液相平衡相图对于真空蒸馏生产实践以及废弃二次资源回收分离提纯具有重要的实际意义。本文首先介绍了合金体系的分离系数,然后介绍了气液相平衡成分图的计算方法,并指出了其不足,接着介绍了气液平衡相图的计算方法,同时给出了理论计算与实验值存在偏差的原因。     

EuCl_3—PbCl_2二元系相图的研究

ＥｕＣｌ_３—ＰｂＣｌ_２二元系相图的研究张俊卿，李玉生，吴志华，王明生（包头钢铁学院冶金系包头０１４０１０）相图是材料科学研究的基础。人们为了得到在特定条件下使用的材料，都必须从相图上了解材料可能存在的条件或从中得到发展新材料的启示。研究稀土熔盐体系...     

镁合金板材研究获重要进展

近期，中科院金属研究所材料环境腐蚀研究中心韩恩厚、陈荣石研究员带领博士生闫宏、吴迪在镁合金相平衡热力学原理和相图计算基础上，通过添加适量的稀土元素，如Y、Nd、Gd等，优化轧制工艺、中间退火和轧制后的最终退火工艺，研究了一系列Mg—Zn—RE合金轧制板材的组织、织构和各向异性。     

根据二元合金相图计算脱氧元素的熔化热

根据9幅二元合金相图，分别计算了6种炼钢用脱氧元素Si、Ca、Ba、Mn、La和Al的熔化热。根据二元合金相图计算脱氧元素的熔化热的方法，对确定出钢温度和钢水脱氧过程的热力学分析及计算有一定的实际意义。     

简单共晶系相图的计算机计算

根据热力学原理和热力学数据，用计算机计算和绘制了一些简单共晶系相图，并用计算机打印相应的部分相图数据。     

Experimental Study and Thermodynamic Optimization of the FeO-V_2O_3 System

Optimization of the phase diagram of FeO-V2O3 system is a part of an on-going research project to develop a self-consistent multi-component thermodynamic database for vanadium slag from hot metal.Due to the lack of experimental data for optimization,a novel experimental investigation has been carried out by thermal analysis(DSC)with a series of slags on different V2O3 contents(i.e.3mass%-12mass%).All available thermodynamic and phase diagram data for the binary systems have been simultaneously optimized with CALPHAD(Calculation of Phase Diagrams)methods to give one set of model equations for the Gibbs free energy of the liquid slag as functions of composition and temperature.The modified quasi-chemical model was used to describe the binary slag system.It was demonstrated that the calculated phase diagram with the optimized parameters was in good agreement with the experimental data.     

Experimental Study and Thermodynamic Optimization of the FeO-V203 System

Optimization of the phase diagram of FeO-V20a system is a part of an on-going research project to develop a self-consistent multi-component thermodynamic database for vanadium slag from hot metal. Due to the lack o{ ex- perimental data for optimization, a novel experimental investigation has been carried out by thermal analysis （DSC） with a series of slags on different V2 03 contents （i. e. 3mass%- 12mass%）. All available thermodynamic and phase diagram data for the binary systems have been simultaneously optimized with CALPHAD （Calculation of Phase Dia- grams） methods to give one set of model equations for the Gibbs free energy of the liquid slag as functions of compo- sition and temperature. The modified quasi-chemical model was used to describe the binary slag system. It was dem- onstrated that the calculated phase diagram with the optimized parameters was in good agreement with the experi- mental data.     

Thermodynamic Assessment of DyCl3-MCl （M= Na, K, Rb, Cs） Systems

Using the CALPHAD （Calculation of Phase Diagram） technique, the DyCl3-MCl （M = Na, K, Rb, Cs） systems were optimized and calculated. The modified quasi-chemical model in the pair approximation for short-range ordering was used to describe the Gibbs energies of the liquid phase in these systems. From the measured phase diagram data and experimental thermodynamic properties, a series of thermodynamic functions were optimized base on an interactive computer-assisted analysis. The optimized parameters and the experimental data were thermodynamically self-consistent. The optimized results were discussed.     

MNO_3–Ca(NO_3)_2 (M=Li,Na,K)二元相图的热力学优化

基于CALPHAD方法对MNO3-Ca(NO3)2(M=Li,Na,K)二元相图的试验数据首次进行了热力学优化拟合,得到了3个二元相图的过量混合热力学性质的参数及Ca(NO3)2的熔化吉布斯自由能随温度变化的函数表达式,并用拟合的参数计算了3个二元相图,最后将计算得到的相图与试验相图进行了比较。     

Thermodynamic optimization and calculation of phase diagrams of YbCl3-MCl (M=Na, K, Rb, Cs)

YbCl3-MCl (M = Na, K, Rb, Cs) systems were optimized and calculated using the CALPHAD (CALculation of PHAse Diagram) technique. The modified quasi-chemical model in the pair-approximation for short-range ordering was used to describe the Gibbs energies of liquid phase in the systems. On the basis of the measured phase diagram data and experimental thermodynamic properties, a series of thermodynamic functions were optimized and calculated through an interactive computer-assisted analysis. Furthermore, some reasonable discussions on the thermodynamic parameters for these strong interaction binary systems were carried out. The results showed that the optimized parameters and experimental data are thermodynamically self-consistent.     

Phase equilibria and thermodynamics of binary copper systems with 3d-metals. I. The copper-scandium system

Thermodynamic assessment of the Cu-Sc system was carried out using the CALPHAD method. A set of self-consistent model parameters was obtained with the usage of the information about phases equilibria and thermodynamic. Gibbs energy for the liquid phase was assessed within the framework of the model of ideal associated solution. Optimized model parameters make it possible to reproduce satisfactorily the phase diagram and thermodynamic values. Analysis of the relative thermodynamic stability of supercooled melts and competing crystalline phases let us to predict their glass forming ability by rapid quenching from the liquid state. __________ Translated from Poroshkovaya Metallurgiya, Nos. 3–4(448), pp. 43–55, March–April, 2006.     

Al-Zn(Cu)合金的相变和Al-Zn-Cu系相图

Al-Zn-Cusystemistheimportantbasisfor practicalAlalloysandZnalloys[1].Amiscibility gapofthefccphaseexistsabove277℃inthe Al Znsystem[2].Thealloywhosecompositionis atthetopofthemiscibilitygapiscalledsym metricalalloyAlZn.Thisalloyhasmanytypical properties.Theimportantoneisthatthespi nodaldecompositioneasilytakesplaceinit.In ordertoavoidthedecomposition,Cuhasbeen added,whichiseffective.Additionof2%Cu molefractioncoulddelaythespinodaldecompo sitionfortwogrades[3,4].AlZn 2Cuisanalloy which…