液相沉淀法制备VO2纳米粉及晶化过程研究

研究了以VOSO4为前驱体，应用液相沉淀法制取VO2纳米粉的制粉技术以及VO2粉末的晶化过程，采用TGA，DSC，XRD，TEM等测试手段对所得粉的物理特性进行了测试分析。试验结果表明：所制取的VO2粉末颗粒粒径介于10nm-30nm之间，该粉体经400％真空热处理10h可完全实现晶化，相变温度为65％。     

过冷金属熔体中枝晶生长的相场法模拟

采用相场模型和有限差分法，模拟了过冷金属熔体的枝晶生长，系统研究相场模型中相场和温度场耦合系数（λ）、热扩散系数（DT）以及界面原子运动时间参数（T0）对枝晶形貌的影响。模拟结果表明，随着相场和温度场耦合系数的增大，晶粒形貌由紧实枝晶向海藻态转变；随着热扩散系数和界面原子运动时间参数的增大．晶粒形貌由光滑枝晶向紧实枝晶转变。     

瞬间液相扩散连接模型及发展现状

瞬间液相扩散连接（TLP-DB）方法以其独有的性能优势，在先进材料连接领域得到广泛的重视和应用。综述了瞬间液相扩散焊中接触熔化、液相均匀化、等温凝固以及固相成分均匀化阶段的理论模型及发展状况．并对现有模型进行了分析和讨论。     

Thermodynamic evaluation of the phase equilibria and glass-forming ability of the Ti−Be system

The glass-forming ability of Ti−Be alloys is of great interest. Experimental and theoretical evaluations of the glass-forming ability of this binary alloy show that the formation of a metastable TiBe phase with a CsCl-type B2 structure controls the glass-forming ability in this system. However, there is no information on the thermochemical properties of metastable TiBe for the quantitative evaluation of the glass-forming ability using Davies-Uhlmann kinetic formulations. We have carried out a thermodynamic analysis using experimental phase diagram data and the energy of formation of the stoichiometric compounds from ab initio calculations. Furthermore, the Gibbs energy of formation for the body-centered cubic (bcc) phase was evaluated over the entire composition range by applying the cluster expansion method (CEM) to the total energy of some bcc-based ordered structures obtained from ab initio calculations. For the bcc phase, the two-sublattice formalism, (Ti, Be)_0.5(Ti,Be)_0.5, was adopted to describe the A2/B2 transformation. A good agreement between the calculated values and experimental phase equilibria was obtained. Evaluation of the glass-forming ability was also attempted utilizing the thermodynamic quantities obtained from the phase diagram assessment. The calculated glass-forming ability agrees well with the experimental results. This paper was presented at the International Symposium on User Aspects of Phase Diagrams, Materials Solutions Conference and Exposition. Columbus, Ohio, 18–20 October, 2004.     

二元合金过冷液态的形核驱动力和非晶形成能力的热力学分析

利用CALPHAD(calculation of phase diagrams)技术和已有热力学数据,通过对比分析亚稳过冷液态合金中各结晶相的形核驱动力大小,寻找结晶能力弱而非晶形成能力强的成分范围.选择典型的非晶形成体系,以平衡相图中共晶深度明显不同的3个二元合金体系Cu-Zr,Ni-Nb和Pd-Si为研究对象,预测各体系非晶形成能力与成分的关系,获得非晶形成最优成分,并与共晶点成分及实验数据进行对比.预测结果与实验确定的块体非晶最优成分相符.     

非晶液相法生产烧结钕铁硼磁体的优越性

探讨了使用非晶态液相和接近２：１４：１成分的主相的双相合金工艺制造烧结钕铁硼稀土永磁材料的优越性。表明非晶液相法能有效减少钕铁硼磁体制造过程中的氧化,其他工艺相同时可获得比单相法更高的磁性能。暴露操作也可容易地制取Ｎ４０商业档次的磁体。在一定的封闭保护条件下,很容易获得氧含量极低、性能达Ｎ４５商业水平的磁体。     

Zr-Ti-Cu-Ni-Be大块非晶合金等温晶化过程相分离研究

利用差示扫描量热法(DSC)和透射电镜(TEM)对Zr41.2Ti13.8Cu12.5Ni10Be22.5(at％)大块非晶合金的等温晶化过程和析出相进行了研究。结果表明，大块非晶合金在等温晶化过程中表现出多阶段相析出行为，并且在不同的晶化阶段，析出相也有所不同。在第1个晶化阶段，析出相主要是体心四方(b.c．t)结构的Zr2Cu相；而在晶化的第2个阶段，晶化相主要为简单六方结构的ZrBe2相。从一定程度上证实了Zr41.2Ti13.8Cu12.5Ni10Be22.5大块非晶合金在发生晶化时会形成富Zr区和富Be区，即有相分离的趋势。XRD测试的结果也证实了非晶合金在发生完全晶化时，主要的晶化产物为Zr2Cu和ZrBe2相。     

Thermodynamic Study of Liquid,Crystalline and Quasi-Crystalline Al-Mn Phases

Thermodynamic properties of liquid, intermetallic, and quasi-crystalline phases of the Al-Mn system have been studied using two experimental techniques: integral effusion method and Knudsen-cell mass spectrometry. The functions of the liquid phase followed the laws of associated solution and indicated that three type complexes, AlMn, Al₂Mn, and Al₅Mn, existed in the melt. Phase equilibria calculated using this model and the intermetallic compounds thermodynamic characteristics were in close agreement with phase diagram. The decagonal phase was found to be more stable than the icosahedral quasi-crystals. The calculated enthalpies of the quasi-crystalline phase transformation to the equilibrium crystals were close to the available literature information. The difference between the Gibbs energies of both type quasi-crystals and equilibrium crystalline compositions increases with decreasing temperature. This evidence favors the conclusion that the stabilization of quasi-crystals is entropic in nature and that the quasi-crystalline state, similar to the glassy state in metallic alloys, is only intermediate between liquid and crystals. The conditions of the quasi-crystals formation were found to be closely related to a certain type of the chemical short-range order in liquid, namely to significant mole fraction of the Al₅Mn associative complexes.     

Liquid phase separating mechanism and preparation techniques of immiscible alloys

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采用相场法研究多相粉末的烧结过程（英文）

针对多相粉末体系,建立描述其烧结过程的相场模型。在该模型中,界面由不同成分的各相混合组成,通过热力学平衡确定界面中各相的成分;除了体扩散之外,也同时考虑了界面扩散和表面扩散。所建的模型被应用到Fe-Cu粉末的烧结过程。结果表明,该模型能够定量地描述烧结过程中的微观组织演变以及溶质扩散等现象。     

液相合成铌酸钾粉体的研究

以Nb2O5、KECO3、HF和（NH4）2C2O4为原料，以柠檬酸为配位剂，乙二醇为酯化剂，用氨水调节溶液的pH值，首先将Nb2O5在水浴条件下溶于HF，加入（NH4）2C2O4和氨水获得沉淀物，而后用柠檬酸溶解获得Nb-柠檬酸溶液。K2CO3与Nb-柠檬酸溶液在乙二醇的交联作用下形成了K-Nb凝胶前驱体。用XRD和SEM研究了不同pH值、不同柠檬酸与金属离子的摩尔比条件下所形成的凝胶前驱体在不同温度下煅烧所得粉体的相组成和形貌。研究发现当柠檬酸与金属离子的摩尔比为3：1，柠檬酸和乙二醇的摩尔比为1：2时，可形成稳定的K-Nb前驱体溶液和凝胶。分析结果表明，K-Nb凝胶前驱体在加热过程中分解成K2CO3相，K2CO3与Nb-柠檬酸溶液发生反应生成KNbO3凝胶，凝胶经800℃煅烧3h或160℃水热反应8h可以制备出颗粒分布均匀的纯钙钛矿型KNbO3粉体。IR谱表明。800℃煅烧或160℃水热反应都出现了Nb-O的特征峰。     

Wilson方程对二元铝基液态合金组元热力学性质的预测

描述了Wilson方程在二元铝基液态合金各组元热力学性质计算中的应用 ,介绍了Wilson方程在热力学计算中的优势。同时为预测二元铝基液态合金中各组元的热力学行为提供了一种很好的方法 ,并为实际生产过程的理论分析提供了有用的热力学模型。     

含镉酸洗废液的治理研究

通过对某厂贵金属车间在生产过程中产生的含镉酸洗废液,进行治理试验研究,得出了通过蒸馏、电解的方法,可以实现含镉酸洗废液的回收利用,达到了闭路循环的目的。同时,对蒸馏液的回用以及电解电流、电解液浓度、酸度对电解的影响,进行了讨论,确定了工艺过程的最佳操作参数。     

铬铁矿熔盐液相氧化新反应系统的热力学分析

利用自编的热力学计算软件对铬铁矿熔盐液相氧化过程进行了热力学计算与分析，通过与传统铬盐生产方法中的碳酸钠高温氧化焙烧过程的比较表明，在较低温度下，液相氧化新过程具有很强的反应趋势，大的放热量及极宽的反应条件，大大优于现行铬盐生产的传统焙烧过程。