STATISTICAL THEORY OF MOLTEN SALT SOLUTIONS Ⅳ. PHASE EQUILIBRIUM OF A_2B-AC-AD-AE SYSTEMS

根据我们以前提出的熔盐溶液的统计模型和零级近似规则溶液理论,导出了A_2B-AC-AD-AE型四元同离子系相图中A_2B初晶温度的计算方法.计算结果与若干实测数据符合较好。     

STATISTICAL THEORY OF MOLTEN SALT SOLUTIONS Ⅰ. ENERGY OF MIXING OF BINARY SYSTEMS

本文根据熔盐的径向分布函数理論,对于含一价离子的二元熔盐溶液,提出了三度空間的熔盐溶液統計模型。根据这一模型导出了計算二元熔盐系混合热、混合过剩自由能和某些二元相图液相线的公式,并利用这些公式对各种碱金属硝酸盐和卤化物的二元溶液作了計算,計算結果与实測值颇为符合。     

STATISTICAL THEORY OF MOLTEN SALT SOLUTIONS Ⅱ. ENERGETIC PARAMETER OF SOLUTION OF BINARY SYSTEMS

提出了熔盐溶液的溶解能参数的概念,熔盐系A_nB_m-A_(n′)C_(m′)(A离子之价数为Z)的溶解能参数为: f(r)=Z~2nn′/m(r_A+r_B)+Z~2n′~2/m′(r_A+r_C)-2Z~2nn′/(2r_A+r_B+r_C)(n′/nm′+1/m) 熔盐系A_nB_m-C_(n′)D_(m′)(C离子之价数为Z′)的溶解能参数为: f(r)=n′Z′Z(n+(nZ/n′Z′)m′/m′(r_A+r_D)+nZZ′(m+nZ/Z′)/m(r_B+r_C)-nZ~2(n+m)/m(r_A+r_B)-n′Z′Z(n′+m′)/m′(r_C+r_D)。 溶解能参数是熔盐静电混合能的近似函数,当f(r)为正值时,溶液呈现负偏差,当f(r)为负值时,溶液呈现正偏差,f(r)可作为估计熔盐溶液的热力学性质和二元熔盐相图的近似方法。     

FORMABILITY OF TERNARY INTERMEDIATE COMPOUNDS IN SOME MOLTEN SALT PHASE DIAGRAMS

ＦＯＲＭＡＢＩＬＩＴＹＯＦＴＥＲＮＡＲＹＩＮＴＥＲＭＥＤＩＡＴＥＣＯＭＰＯＵＮＤＳＩＮＳＯＭＥＭＯＬＴＥＮＳＡＬＴＰＨＡＳＥＤＩＡＧＲＡＭＳ￥Ｋａｎｇ，Ｄｅｓｈａｎ；Ｗａｎｇ，Ｘｕｅｙｅ；Ｙａｏ，Ｓｈｕｗｅｎ；Ｃｈｅｎ，Ｎｉａｎｙｉ（Ｓｈａｎｇｈａｉ...     

PHASE DIAGRAM OF Bi-Pb-T1 TERNARY SYSTEM

Isothermal section at 25℃ of phase diagram and phase structure of Bi-Pb-Tl ternary systemhave been studied by means of room and high temperature X-ray diffraction and quenching.     

PHASE EQUILIBRIUM RELATIONSHIPS OF α_2(α)/γ IN THE Ti-Al-Cr TERNARY SYSTEM

采用扩散偶－电子探针法系统测定了Ｔｉ－Ａｌ－Ｃｒ三元系１０００－１３００℃的α２（α）／γ相平衡关系和相平衡成分,给给出Ｃｒ含量小于１０％（原子分数）范围的Ｔｉ－Ａｌ－Ｃｒ三元系局部等温截面和Ｔｉ－Ａｌ局部纵截面相图,明确了Ｃｒ在α２（α）和γ相中分配比的变化规律,研究结果支持Ｃｒ在γＴｉＡｌ相中取代Ａｌ的位置,降低γ－ＴｉＡｌ相中Ａｌ含量的观点。     

PREPARATION OF Pb-Ca-Na MASTER ALLOY USING MOLTEN CHLORIDE SALT ELECTROLYSIS

ＰＲＥＰＡＲＡＴＩＯＮＯＦＰｂ－Ｃａ－ＮａＭＡＳＴＥＲＡＬＬＯＹＵＳＩＮＧＭＯＬＴＥＮＣＨＬＯＲＩＤＥＳＡＬＴＥＬＥＣＴＲＯＬＹＳＩＳＳｏｎｇＲｅｎｙｉｎｇ；ＷａｎｇＸｉｎｇｊｉｅ；ＬｕｏＳｈｕｍｅｉ；ＪｉａｎｇＣｈａｎ；ＴａｎｇＤｉｎｇｘｉａｎｇ（...     

MOLECULAR DYNAMICS STUDY OF STRUCTURE IN MOLTEN SALT SOLUTION NaF-CaF_2

The NaF-CaF_2 system has been studied by molecular dynamics simulation.The paircorrelation functions between cations and anions and the bond angle distributions ofcation and anion triplets have been obtained.The bridging and complexing in the systemare discussed based on the pair correlation functions and bond angle distributions.Theresults simulated show that the F~- ions around a Ca~(2+)ion do not form tetrahedroncoordination,so some of small complexing clusters such as CaF_4~(2-)are hardly found.Apossible structure of F~- ions around Ca~(2+)ions is that three Ca~(2+)ions constitute anequilateral triangle through three Ca-F-Ca bridges and two F~- ions are located overand under the center of the right triangle,respectively.Meanwhile,on the outside of thetriangle,every Ca~(2+)ion has other two F~- ions as its neighbors.     

PHASE EQUILIBRIUM OF SBCL_3-HCL-H_2O SYSTEM

ＰＨＡＳＥＥＱＵＩＬＩＢＲＩＵＭＯＦＳｂＣｌ３－ＨＣｌ－Ｈ２ＯＳＹＳＴＥＭＤｕａｎ，Ｘｕｅｃｈｅｎ；Ｚｈａｎｇ，Ｄｕｏｍｏ；Ｚｈａｏ，Ｔｉａｎｃｈｏｎｇ（ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，Ｃｈａｎｇｓｈａ４１００８...     

410℃ ISOTHERMAL SECTION OF Al-Cu-Sb TERNARY SYSTEM PHASE DIAGRAM

本文用X射线粉末衍射法和电子探针法测定了Al-Cu-Sb三元系相图的410℃等温截面。该截面由12个单相区、21个两相区和10个三相区构成。     

LOCAL EQUILIBRIUM METHOD IN STUDYING PHASE DIAGRAM OF Mn-MnO SYSTEM

A special method based on the local equilibrium principle has been introduced in the researchof the phase diagram of Mn-MnO system.With this method,the problems of volatilization ofMn and the corrosion of Mn and MnO to refractory materials were prevented efficiently.Thesolubility of oxygen in Mn and the composition of the interface between MnO and Mn weredetermined.Partial phase diagram of Mn-MnO system were constructed according to pres-ent experimental results.     

PHASE BOUNDARY OF α_2 PRECIPITATION IN Ti-Al-La TERNARY SYSTEM

用透射电镜相分析方法测定了Ti-Al-La三元系在600℃等温截面上α_2相析出相界.结果表明,相界曲线上存在一个Al含量的极大点.根据α_2相形成的电子浓度规律和La的内氧化反应过程,定性地解释了实测相界的走向和Al含量极大点的出现.     

PHASE DIAGRAM OF Nd-Fe-B TERNARY SYSTEM——I.Isothermal Section at Room Temperature

The microstructures of both as-cast and homogenized Nd-Fe-B ternary alloys have beenstudied. The stable phase regions existing in Nd-Fe-B ternary system at room temperaturehave been established by the microzone composition analysis and the phase identification.Based on the obtained results, an isothermal section of Nd-Fe-B ternary system at roomtemperature was drawn.     

α(α2)/γ PHASE EQUILIBRIA IN Ti-Al-C AND Ti-Al-B TERNARY SYSTEMS

α（α２）／γＰＨＡＳＥＥＱＵＩＬＩＢＲＩＡＩＮＴｉＡｌＣＡＮＤＴｉＡｌＢＴＥＲＮＡＲＹＳＹＳＴＥＭＳ①ＬｉＪｕｎｔａｏ，ＨａｏＳｈｉｍｉｎｇＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｒｉｎｇ，Ｎｏｒｔｈｅａｓ...     

PHASE BOUNDARY OF α_2 PRECIPITATION IN Ti-Al-La TERNARY SYSTEM

The phase boundary,of α_2 precipitation at 600℃ in Ti-AI-La ternary system has been de-termined by TEM examination,which shows three kinds of phase regions,namely thesingle α phase region,the transitional phase region where there is superlattice reflection butno α_2 precipitation,and the α+α_2 region.A point of maximum aluminium content was foundto exist on the α/(α+α_2)boundary and the track of the boundary was explained in terms ofthe internal oxidation of lanthanum and the electron concentration rule for α_2 formation.     

APPLICATION OF MOLECULAR ORBITAL THEORY TO ANALYSIS OF PHASE STABILITY FOR ALLOYS

The critical _d vahues ( _ ) of the γ/(γ+σ).γ/(γ+μ) and γ/(γ+γ') phase boundaries insome ternar alloy phase diagrams at various temperatures are calculated by averaging the _d values of sererai selected characteristic points at the phase boundaries.Approxmateequations for the temperature dependence of the critical _d of γ/(γ+σ).γ/(γ+μ) andγ/(γ+γ') phase boundaries are established.The accuracy of the analysis is discussed in detail.It is found for the first time that the average value of the bondorder _ at the phase boundaries ts also approximatelr a constant and therefore a criticalaverage bond order _ like - can be introduced for the analysts of phase stability     

ROOM TEMPERATURE SECTION OF Cu-Dy(≤wt-%)-Ni TERNARY PHASE DIAGRAM

The room temperature section of Cu-Dy(≤35wt-%)-Ni phase diagram has been determinedby means of X-ray diffraction technique.The results are as follows.four single-phase regions(α,Dy_2Ni_(17),DyNi_5 and DyCu_5),five two-phase regions(α+Dy_2N_(17),Dy_2Ni_(17)+DyNi_5,DyCu_5+DyNi_5,α+DyNi_5 and DyCu_5+α)and two three-phase regions(α+Dy_2Ni_(17)+DyNi_5 and α+DyNi_5+DyCu_5)exist in the seetion.No any new phase was ob-servered.The solubility of Dy in α-phase is up to 2 wt-%.     

ISOTHERMAL SECTION OF PHASE DIAGRAM IN Ti-Al-Cr TERNARY SYSTEM AT 1000℃

应用多元扩散偶－电子探针微区分析技术及Ｘ射线衍射分析方法，测定了Ｔｉ－Ａｌ－Ｃｒ三元系相图１０００℃等温截面的含Ａｌ量达７５ａｔ．－％，含Ｃｒ量达７０ａｔ．－％的大部分区域。确定了Ｌｌ２结构的三元化合物相及其成分范围，完整地测定了ＴｉＡｌ，Ｔｉ３Ａｌ，ＴｉＡｌ２及ＴｉＡｌ３的相区范围及相平衡关系，明确了β－Ｔｉ相与ＴｉＣｒ２相的平衡关系及ＴｉＣｒ２相的成分范围     

RELATIONSHIP BETWEEN METASTABLE EXTENSION OF SOLID SOLUBITY OF EUTECTIC SYSTEMS AND PHASE DIAGRAM

A criterion of the metastable extension of solid solubility was proposed.When the eutecticconcentration arm ratio parameter of an alloy,J>10,the hypereutectic extension and themetastable solid solubility limit beyond eutectic concentration may be obtained.When J≤10,the hypoeutectic extension may be obtained.The extension parameter,C_(eq)~s/C_(cu),is directlyproportional to the parameter J.Thus,it seems easy to predict the tendency of the solid solu-hility extension under rapid solidification on the basis of the eutectic phase diagram.     

CALCULATION OF α/γ EQUILIBRIUM PHASE BOUNDARY IN LOW ALLOY STEELS

本文根据现有文献中的数据,将Sharma等的规则溶液模型推广到多元系,计算了含Cr,Mn,Si的20Cr,30Cr,40Cr,40Mn2,20CrMn,35CrMn2,38Crsi以及30CrMnSi等低碳低合金钢在其两相区各温度下α和γ两相的平衡浓度、两相的相对量及A_(e3)温度。计算得到的一系列合金的A_(e3)温度与实验值A_(c3)吻合较好。