Determination of isothermal section of Ni—Pt—Ta ternary system at 1173K

The isothermal section of the Ni-Pt-Ta ternary system at 1173K was determined by means of the diffusion triple technology and the electron microprobe analysis.The phase relations in this system were studied.Linear compound(Ni,Pt)3Ta with small solubility forming between Ni3Ta and Pt3Ta was identified.Four binary compounds,i.e.Pt2Ta,Ni2Ta,NiTa and NiTa2,and four three-phase fields,i.e.Pt2Ta (Ta) NiTa2,Pt2Ta NiTa2 NiTa,Pt2Ta (Ni,PT)3Ta NiTa and (Ni,Pt)3Ta NiTa Ni2Ta,were also identified.     

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。     

773K isothermal section of Gd—Ni—Ti ternary system

The 773K isothermal section of the Gd-Ni-Ti system was investigated b X-ray diffractometry,optical microanalysis and electron probe microanalysis techniques.The results show that it consists of 13 single-phase regions,23 two-phase regions and 11 three-phase regions.The maximum solid solubility of Ti in Ni,Gd2Ni17,GdNi5 and Gd2Ni7 are 6.0%,3.0%,3.0%,and 2.5(mole fraction).respectively.     

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.     

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.     

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.     

Ni-Cr-Mo三元系1358 K等温截面的测定

应用三元扩散偶技术测定了Ni-Cr-Mo三元系1358 K的等温截面,借助电子探针微区成分分析方法分析了Ni-Cr-Mo三元扩散偶的相区成分,并对其相关系进行了研究.测得Ni-Cr-Mo三元扩散偶在1358 K下存在一个中间化合物NiMo,Cr和Mo在扩散偶中形成连续固溶体,Ni和（Cr,Mo）有限固溶,扩散偶中未发现三元中间化合物.实验发现Ni-Cr-Mo三元系1358 K的等温截面存在一个三相区：Ni＋NiMo＋（Cr,Mo）.     

1 100 ℃ isothermal section of Nb-W-Zr-C quaternary system

An isothermal section of the Nb-W-Zr-C system at 1 100 ℃ was established by means of multiphase dif fusion couples along with electron microprobe analysis and X-ray diffraction analysis. The isothermal section consists of two single-phase regions, a(Nb, W, Zr) and (W, Nb)2Zr and one double-phase region, a(Nb, W, Zr) (W, Nb)2Zr. It is concluded that (W, Nb)2Zr is an interstitial intermediate phase with the face-centered cubic (Cu2Mg) lattices. The maximum solid solubility of carbon in (W, Nb)2Zr phase is determined as about 4. 18%C (mole fraction). The composition ranges of tungsten in the (W, Nb)2Zr phase are 55.41% to 65.98 % and the maximum solid solubility of niobium in (W, Nb)2Zr is determined as 7.78%.     

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-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。     

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）。     

Determination of phase equilibria in the Ni-Ta-Zr system at 1223 K

The phase equilibrium relations of the ternary Ni-Ta-Zr system at 1223 K were investigated by means of diffusion triple and electron probe microanalysis (EPMA) techniques. Two ternary compounds were found and a series of tie lines and tie triangles have been determined. The maximum solubility of Ta in NiZr2 is about 13.5% (atom fraction). The corresponding tentative isothermal section at this temperature was constructed based on current experimental information.     

Transformations and phase relations in Nb—Ti—Si ternary system at 1373—1473K

1　ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｃａｕｓｅｏｆｔｈｅｉｒｈｉｇｈｓｔｒｅｎｇｔｈ ,ｇｏｏｄｐｌａｓｔｉｃｉｔｙａｎｄｃｏｒｒｏｓｉｏｎｒｅｓｉｓｔａｎｃｅ ,ｅｓｐｅｃｉａｌｌｙｌｏｗｄｅｎｓｉｔｙａｎｄｅｘｃｅｌｌｅｎｔｆｒａｃｔｕｒｅｔｏｕｇｈｎｅｓｓ ,     

Partial phase diagram of Au-Ag-Dy ternary system

On the basis of Au-Ag, Au-Dy and Ag-Dy binary phase diagrams, the 700 ℃ isothermal section of Au-Ag-Dy ternary system（Dye≤35 %, mole fraction） was established by X-ray diffraction analysis, differential thermal analysis and optical microscopy. It is found that there is a long single-phase region, Au（Ag） or Ag（Au）, along the Au-Ag binary isomorphous system on the gold-silver-rich side of the 700 ℃ isothermal section and between the binary compound Au2Dy and Ag2 Dy there is the all proportional solid solution, （Au2 Dy） or （Ag2 Dy）. It is confirmed that the partial 700 ℃ isothermal section consists of six single-phase regions： solid solution Au（Ag） or Ag （Au）, （Au2 Dy） or （Ag2 Dy）, Au6 Dy, Au51 Dy14, Au3 Dy and Ag51 Dy14 ; nine binary-phase regions; （Au2 Dy） ＋ Au （Ag）, Au6Dy＋ Au（Ag）, Au（Ag） ＋Ag51 Dy14 , Ag51 Dy14 ＋ （Au2Dy）, Au3Dy＋（Au2Dy）, Au3Dy＋ Au51 Dy14, Au51 Dy14＋Au6Dy, Au51 Dy14＋Au（Ag） and Au（Ag） ＋Au3Dy; four ternary regions： Ag51 Dy14＋ （Au2Dy）＋ Au （Ag）, （Au2 Dy） ＋ Au（Ag） ＋ Au3 Dy, Au（Ag） ＋ Au3 Dy＋ Au51 Dy14 and Au51 Dy14＋ Au （Ag）＋ Au6 Dy. No new ternary compound is formed in the gold-silver-rich field（Dy≤35 %） of the Au-Ag-Dy ternary system.     

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。     

Investigation on the isothermal section of the Gd-Ni-Y ternary system at 773 K

The isothermal section of the phase diagram of the Gd-Ni-Y ternary system at 773 K was investigated by means of X-ray powder diffraction, metallographic analysis and scanning electron microscopy with energy dispersive analysis. The isothermal section consists of 12 single-phase regions, 15 two-phase regions and 4 three-phase regions. Six pairs of corresponding compounds in the Gd-Ni and Y-Ni systems, i.e., Gd₂Ni₁₇ and Y₂Ni₁₇, GdNi₅ and YNi₅, Gd₂Ni₇ and Y₂Ni₇, GdNi₃ and YNi₃, GdNi₂ and YNi₂, Gd₃Ni and Y₃Ni and metals Gd and Y form a continuous series of solid solutions, respectively. At 773 K, the maximum solubilities of Gd in YNi and Y in GdNi were about 20 at.% Gd and 8 at.% Y, respectively. No solubility of Gd in YNi₄ and Y in GdNi₄ was 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.     

Isothermal section at 927℃ of Cr-Ni-Ti system

The isothermal section at 927℃ of the Cr-Ni-Ti system was established using a high-efficiency diffusion couple approach, supplemented with eight equilibrated alloys. The alloy compositions were selected on the basis of the experimental results from the diffusion couple. Both the diffusion couple specimens and the alloys were examined by means of optical microscopy, scanning electron microscopy, and electron probe microanalysis. No ternary compound is found at 927℃. The following five three-phase equilibria are well determined： TiNi3＋（Cr）＋（Ni）, TiNia＋（Cr）＋TiNi, TiNi＋（Cr）＋Cr2Ti, Ti2Ni＋Cr2Ti＋TiNi and Ti2Ni＋Cr2Ti＋（Ti）. The solubilities of Cr in NiTi2, NiTi, and Ni3Ti are determined to be 7.5%, 14.5% and 11.4% （molar percent）, respectively, α-Cr2Ti and β-Cr2Ti dissolve about 9.2% and 13.9% Ni （molar percent）, respectively.     

The 773 K isothermal section of the Nd–Ni–V ternary system

The 773 K isothermal section of the phase diagram of Nd–Ni–V ternary system was investigated by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) techniques. There are in total 14 single-phase regions, 25 two-phase regions and 12 three-phase regions in the 773 K isothermal section. The maximum solid solubilities of V in Ni, NdNi₅, Nd₂Ni₇ and NdNi₂, is about 16.5 at.% V, 2.0 at.% V, 1.0 at.% V and 3.0 at.% V at 773 K, respectively, and that of Nd in Ni, Ni₃V, Ni₂V, Ni₂V₃, NiV₃ and V does not exceed 1 at.% Nd. No ternary compounds have been observed in this work.