Ni-Fe-Mo三元系1373K等温截面的研究

采用三元扩散偶技术测定了Ni—Fe—Mo三元系1373Ni—Fe—Mo三元扩散偶的相区成分，并对其相关系进行了研究。K的等温截面，借助电子探针微区成分分析方法分析了测得Ni-Fe-Mo三元扩散偶在1373K下存在2个二元中间化合物：μ和NiMo。该三元系在1373K存在3个三相区：μ＋bcc（Mo）＋NiMo；μ＋NiMo＋fcc；bcc（Fe）＋μ＋fcc：在此温度的扩散偶中未发现三元中间化合物。     

Ni-Mo-Re三元系1473K等温截面的研究

采用三元扩散偶技术测定了Ni-Mo-Re三元系1473 K的等温截面,借助电子探针微区成分分析方法分析了Ni-Mo-Re三元扩散偶的相区成分,并对其相关系进行了研究.Ni-Mo-Re三元扩散偶在1473 K时存在3个二元中间化合物:X,σ和NiMo,在此温度的扩散偶中未发现三元中间化合物.经分析,Ni-Mo-Re三元系在1473K存在4个三相区:Re Ni X;Ni NiMo σ;σ X Ni;σ Mo NiMo.     

β钛合金的研究进展

采用扩散偶技术测定了Fe-Ni-Nb三元系1198 K的等温截面,借助电子探针微区成分分析方法对Fe-Ni-Nb三元扩散偶的相区成分,及相关系进行研究.结果表明:Fe-Ni-Nb三元扩散偶在1198 K时生成μ,Fe2Nb,Ni6Nb7和Ni3Nb 4个中间化合物.μ相与Ni6Nb7形成连续固溶体,表示为(Fe,Ni)6Nb7.该等温截面形成γ(Fe,Ni) Fe2Nb Ni3Nb,Fe2Nb Ni3Nb (Fe,Ni)6Nb72个三相区,没有发现三元化合物.     

Nb-Ti-Co三元系1173K等温截面的研究

采用三元扩散偶技术测定了Nb—Ti-Co三元系富Co，Ti区域在1173K的等温截面，借助电子探针微区成分分析方法测定了Nb-Ti-Co三元扩散偶的相区成分，并对其相关系进行了研究。测得Nb-Ti-Co三元扩散偶富Co，Ti区域在1173K时存在6个二元中间化合物：NbCo3，NbCo2，TiCo3，TiCo2，TiCo和Ti2Co；Nb和Ti形成连续固溶体；在此温度的扩散偶中不形成三元中间化合物。经分析，Nb-Ti—Co三元系在1173K存在6个三相区：（Co）＋TiCo3＋NbCo3，NbCo3＋TiCo3＋NbCo2，NbCo2＋TiCo3＋TiCo2，TiCo2＋NbCo2＋TiCo，NbCo2＋TiCo＋Ti2Co和NbCo2＋Ti2Co＋（Nb，Ti）。     

Nb—Ti—Si三元系1473K等温截面的测定

运用扩散偶技术结合电子探针微区成分分析方法对Nb-Ti-Si三元扩散偶进行相分析，测得Nb-Ti-Si三元系1473K下所生成的7个扩散层，分别是TiSi2,TiSi,Ti5Si3,Nb5Si2和M3Si，此扩散偶中未发现三元化合物，并根据扩散偶中的相区分布和相图中相区分布的关系，得出Nb-Ti-Si三元系1473K下的等温截面。     

Ni—Re—Ta三元系1473K等温截面的测定

应用三元扩散偶技术测定Ｎｉ－Ｒｅ－Ｔａ三元系１４７３Ｋ的等温截面。用电子探针微区成分分析方法对Ｎｉ－Ｒｅ－Ｔａ三元扩散偶进行是得Ｎｉ－Ｒｅ－Ｔａ三元系在１４７３Ｋ下生成ｉ３Ｔａ、Ｎｉ２Ｔａ、ＮｉＴａ、ＮＩＴａ２和ｘ相５个扩散层,在扩散 未发现三元化合物。     

铸钛叶轮气孔,缩孔缺陷的消除

应用多元扩散偶－电子探针微区成分分析技术，研究了Ｔｉ－Ｎｉ－Ｎｂ三元系相图８００℃下的相平衡关系，确定了该三元系相图８００℃等温截面的１２个单相区，２２个两相区和９个三相区。首次给出了Ｔｉ－Ｎｉ－Ｎｂ三元系相图的８００℃等温截面，此外，还确定了４种三元化合物的存在，其中ＸＢ为作者首次发现，其化学计量式为Ｔｉ３Ｎｉ９Ｎｂ８。     

Ti—Ni—Nb三元系相图700℃等温截面

应用多元扩散偶－电子探针微区成分分析技术，测定了Ｔｉ－Ｎｉ－Ｎｂ三元系相图７００℃等温截面，确定了该三元系相图的７００℃等温截面的１２个单相区，２３个两相区和１０个三相区。１２个单相区是：α－Ｔｉ、β－（Ｔｉ，Ｎｂ）、Ｔｉ２Ｎｉ、ＴｉＮｉ、ＴｉＮｉ３、（Ｎｉ）、Ｎｉ３Ｎｂ、Ｎｉ６Ｎｂ７、ＸＡ、ＸＢ、ＸＣ和ＸＤ，其中ＸＢ化合物为首次发现。     

Mg-Nd-Gd三元系723K的等温截面

采用三元扩散偶技术,利用电子探针成分分析,建立Mg-Nd-Gd三元系723 K的等温截面。Mg3Gd和Mg3Nd在三元系中形成连续固溶体（Gd,Nd）3Mg,MgGd和MgNd也形成连续固溶体（Gd,Nd）Mg。在三元系中出现的金属间化合物有 Mg7Gd、Mg5Gd、Mg2Gd、Mg41Nd5、（Gd,Nd）3Mg 和（Gd,Nd）Mg,其中 Mg7Gd 在以往的报道中认为是亚稳相。测量了Mg,、Gd 和Nd在每相中的溶解度,发现在Mg-Nd-Gd三元系中存在4个三相平衡,它们分别是α（Mg）＋Mg7Gd＋Mg41Nd5,Mg7Gd＋Mg5Gd＋Mg41Nd5,Mg5Gd＋Mg41Nd5＋（Gd,Nd）3Mg 和（Gd,Nd）3Mg＋（Gd,Nd）Mg＋Mg2Gd。     

Ti－Ni－Nb三元系相图700℃等温截面

应用多元扩散偶－电子探针微区成分分析技术，测定了Ｔｉ－Ｎｉ－Ｎｂ三元系相图７００℃等温截面，确定了该三元系相图的７００℃等温截面的１２个单相区、２３个两相区和１０个三相区。１２个单相区是：α－Ｔｉ、β－（Ｔｉ，Ｎｂ）、Ｔｉ_２Ｎｉ、ＴｉＮｉ、ＴｉＮｉ_３、（Ｎｉ）、Ｎｉ_３Ｎｂ、Ｎｉ_６Ｎｂ_７、Ｘ_Ａ、Ｘ_Ｂ、Ｘ_Ｃ和Ｘ_Ｄ，其中Ｘ_Ｂ化合物为首次发现。     

Determination of isothermal sections of the Co-Nb-Ni and Ni-Mo-Re ternary systems

The isothermal sections of the Co-Nb-Ni ternary system at 1373 K and the Ni-Mo-Re ternary system at 1473 K were determined by means of diffusion triple and electron probe microanalysis (EPMA).The results indicate that there are three three-phase regions found in the Co-Nb-Ni ternary system at 1373 K:(Ni,Co) NbCo3 Ni3Nb,NbCo3 NbCo2 Ni3Nb,and NbCo2 μ Ni3Nb;and four three-phase regions found in the Ni-Mo-Re ternary system at 1473 K:Re Ni χ,Ni NiMo σ,σ χ Ni,and σ Mo NiMo.No ternary eompoond is observed in the two isothermal sections.The isothermal sections arc contrasted with the previous study.     

Determination of isothermal sections of Ni-Cr-Nb ternary system

The isothermal sections of Ni-Cr-Nb ternary system at 1 323 K and 1 423 K were determined by means of diffusion triple and energy spectrum analysis (ESA). By analyzing the diffusion layers in the diffusion couples, the compounds forming in this system were identified. There are three similar compounds found at these two temperatures: Ni3 Nb, NiNb and NbCr2-R, and four similar three-phase regions are found : (Ni) (Cr) Ni3 Nb, Ni3Nb NbCr2-R NiNb, NbCr2-R (Cr) Ni3 Nb, NbCr2-R NiNb (Nb). The results show that no phase transformation happens between these tow temperatures. But the solid solubilities of the binary compounds at 1423 K become bigger than those at 1 323 K, especially the solid solubility of NbCr2-R. No ternary compound is observed.     

Determination of Isothermal Section of Fe-Ni-Zr Ternary System at 1198K

The isothermal section of Fe-Ni-Zr ternary system at 1198K was experimentally determined using diffusion triple technique together with scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The results indicate that there are seven binary intermetallic phases, Fe2Zr, FeZr2, NiZr2, NiZr, Ni10Zr7, Ni7Zr2, and Ni5Zr, found in the ternary system, the binary compounds NiZr2 and FeZr2 show a homogeneity range and form a continuous solid solution, namely (Fe, Ni)Zr2. Five three-phase sections, γ(Fe,Ni) Ni7Zr2 Ni5Zr, γ(Fe,Ni) Ni7Zr2 Ni10Zr7, γ(Fe,Ni) Fe2Zr Ni10Zr7, (Fe,Ni)Zr2 Fe2Zr Ni10Zr7, and (Fe,Ni)Zr2 NiZr Ni10Zr7, exist in the isothermal section. No ternary compound is observed.     

DETERMINATION OF PHASE EQUILIBRIA OF Al-Ni-Ti SYSTEM AT 1200 K

ＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＰＨＡＳＥＥＱＵＩＬＩＢＲＩＡＯＦＡｌＮｉＴｉＳＹＳＴＥＭＡＴ１２００Ｋ①ＸｕＨｏｎｇｈｕｉ，ＪｉｎＺｈａｎｐｅｎｇＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｒｉｎｇ，ＣｅｎｔｒａｌＳ...     

La-Ni-Cr三元系600℃等温截面的相关系

用X射线粉末衍射法，差热分析法和金相分析法测定了La-Ni-Cr三元系600℃等温截面的相关系。结果表明：此截面由10个单相区、17个两相区和8个三相区组成。在本实验条件下未发现新的三元化合物，没有观察到化合物Cr，Ni3和Cr3Ni2的谱线；化合物La3Ni的谱线是由La和La7Ni3的谱线相叠加；没有观察到LaNi2，而观察到La7Ni16的存在。Ni在Cr中的最大固溶度大约为3at％，Cr在Ni，LaNi5，La2Ni7，LaNi3，La2Ni3，LaNi和La7Ni3中的最大固溶度(at%)分别约为35，20，15，8，9，9和6，Cr在La7Ni16中的固溶度几乎为零。     

Microstructural evolution mechanism during brazing of Hastelloy X superalloy using Ni–Si–B filler metal

The paper aims at understanding solidification phenomena and solid state precipitations during diffusion brazing of Hastelloy X nickel base superalloy using a ternary Ni–4.5Si–3.2 B (in wt-%) filler metal. The joint is featured by the formation of Ni-rich solid solution in an isothermal solidification zone, borides/silicide formation during eutectic-type solidification in an athermal solidification zone, on-cooling precipitation of fine nickel silicides in the joint centerline, in situ precipitation of Mo–Cr-rich borides in the diffusion affected zone and grain growth in the heat affected zone. The implication of the phase transformations on the joint properties is discussed. It is shown that Hastelloy X exhibited very fast isothermal solidification which can be attributed to its high Mo and Cr content that promotes in situ boride precipitation during brazing.     

Determination of the 850 °C isothermal section in the Co-Ni-Ti system

The isothermal section of the Co-Ni-Ti system at 850 °C was determined by using diffusion couple specimens and equilibrated alloys, which were analyzed by optical microscopy, X-ray diffraction (XRD), and electron probe microanalysis (EPMA) techniques. This isothermal section consists of 9 single-phase regions, 12 two-phase regions, and 4 three-phase regions. The 9 single-phase regions include αTi solid solution, βTi solid solution, Ti₂(Co, Ni), Ti(Co, Ni), fcc-(Co, Ni) solid solution, and solid solutions based on TiCo₂(hexagonal), TiCo₂(cubic), TiCo₃, and TiNi₃. No ternary Co-Ni-Ti compound was found.