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Phase equilibria of the Cr-Mo-Ru ternary system at 1100 °C and 1200 °C have been experimentally investigated using electron probe microanalyzer and x-ray diffraction. The σ-Cr2Ru forms a σ-(Mo5Ru3, Cr2Ru) continuous solid solution phase with the σ-Mo5Ru3 phase at 1200 °C, but not at 1100 °C. The BCC (Cr, Mo) continuous solid solution phase exists at both 1100 °C and 1200 °C. Based on the measured experimental results and the thermodynamic parameters of the three binary sub-systems, a set of self-consistent parameters of the Cr-Mo-Ru system was evaluated using the CALPHAD method. Several vertical sections, isothermal sections, and liquidus surface projection of the Cr-Mo-Ru ternary system were calculated in this study. The results of phase equilibrium experiments and thermodynamic calculations show that although the solid solubility of the σ phase in the Cr-Mo and Mo-Ru binary systems is relatively small, it is exceptionally large in the Cr-Mo-Ru ternary system. The current obtained thermodynamic parameters of the Cr-Mo-Ru ternary system can provide the essential information and support for the theoretical guidance on the design of the Ni-based multi-component superalloys. [ABSTRACT FROM AUTHOR]

Three natural geological glasses (andesitic glass OJY‐1, and rhyolitic obsidians OH‐1 and OA‐1) of specimen sizes 50–150 g were characterised as reference materials for in situ microanalysis of major and trace elements, and Pb isotope ratios. Utilised techniques include isotope‐dilution analyses by TIMS and MC‐ICP‐MS, bulk analyses by XRF, ICP‐OES, ICP‐MS, and microanalysis (10–120 μm spot size) by electron probe microanalyser, LA‐ICP‐MS and LA‐MC‐ICP‐MS. Microanalyses (10–120 μm) indicate that all three glasses are homogeneous with respect to fifty‐four out of fifty‐eight determined elements and Pb isotope ratios, except for Ni in OJY‐1, and Cu, Zr and Ce in OH‐1. The determination of reference values as well as their uncertainties at the 95% confidence level closely followed International Organization for Standardization (ISO) guidelines and the certification protocol of the International Association of Geoanalysts (IAG). These three glasses are fully natural without any subsequent heat treatment, and they represent useful additions to the widely distributed MPI‐DING, USGS and CGSG reference glasses for microanalytical techniques such as electron probe microanalysis, μ‐XRF, LA‐ICP‐MS and SIMS. [ABSTRACT FROM AUTHOR]

In this work, two isothermal sections of the Co-Ta-Si ternary system at 900 °C and 1100 °C are constructed in the whole composition range via phase equilibrium determination with the help of electron probe microanalysis (EPMA) and X-ray diffraction (XRD) techniques. Firstly, several reported ternary phases G (Co16Ta6Si7), G″ (Co4TaSi3), E (CoTaSi), L (Co3Ta2Si) and V (Co4Ta4Si7) are all re-confirmed again. The G″ phase is found to be a kind of high-temperature compound, which is unstable at less than 1100 °C. Additionally, the L phase with a large composition range (Co32–62Ta26–36Si10–30) crystallizes with a hexagonal crystal structure (space group: P63/mmc, C14), which is the same as that of the binary high-temperature λ1-Co2Ta phase. It can be reasonably speculated that the ternary L phase results from the stabilization toward low-temperature of the binary λ1-Co2Ta through adding Si. Secondly, the binary CoTa2 and SiTa2 phases are found to form a continuous solid solution phase (Co, Si)Ta2 with a body-centered tetragonal structure. Thirdly, the elemental Si shows a large solid solubility for Co-Ta binary compounds while the Ta and Co are hardly dissolved in Co-Si and Ta-Si binary phases, respectively. [ABSTRACT FROM AUTHOR]

In this study, the isothermal sections of the Co-Nb-Re ternary system at 1200, and 1300 °C have been experimentally determined combining the means of electron probe microanalysis (EPMA) and x-ray diffraction (XRD). The obtained experimental results showed that: (1) The Laves phase of λ3-Co2Nb (C36) was stable at 1300 °C. The temperature was beyond its stability limit in Co-Nb binary system. (2) The solubility of Re in the λ3 phase was so large that the nearest λ2-Co2Nb (C15) phase was essentially surrounded. (3) The solubility of Re in the μ-Co7Nb6 phase was 34.0 at.% at 1200 °C and 35.2 at.% at 1300 °C, respectively. (4) The liquid phase existed at 1300 °C dissolving about 4.0 at.% Re, but it was absent at 1200 °C. (5) The solid solution phase of (εCo, Re) extended from Re-rich to Co-rich side. [ABSTRACT FROM AUTHOR]

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The phase equilibria of the Co-Ti-Ru ternary system at 1000, 1100, and 1200 °C were studied using the electron probe microanalyzer and x-ray diffraction. The results show that: (1) no ternary compound exists in the isothermal sections from 1000 to 1200 °C; (2) the phases of CoTi and TiRu form the continuous solid solution phase (Co,Ru)Ti; (3) the solubility of Ru in the Co3Ti phase is less than 5 at.% at isothermal sections 1000-1100 °C. These experimental results will provide useful information for the foundation for alloy design and the supplement for thermodynamic databases. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Fe-Si-Ti ternary system were investigated by electron probe microanalyzer (EPMA), back scattered electron (BSE) and X-ray diffraction (XRD) on the equilibrated alloys. Twenty-four alloys of the Fe-Si-Ti ternary system were prepared. In this study, three isothermal sections of the Fe-Si-Ti ternary system at 1000, 1100 and 1200 °C were respectively determined and seven ternary compounds were confirmed. The ηFeSi phase is discovered at 1100 and disappeared at 1200 °C. The obtained experimental results show that there is large solubilities of Si in the TiFe phase. The newly determined phase equilibria of the Fe-Si-Ti system will provide useful information for the development of silicon steels. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Mg–Pb–Zn ternary system were investigated using electron probe microanalysis (EPMA), back scattered electron (BSE) imaging and X-ray diffraction (XRD) methods. Three isothermal sections of the Mg–Pb–Zn ternary system at 200 °C, 300 °C and 400 °C were experimentally established. The phase equilibria of Mg–Pb binary and Mg–Pb–Zn ternary system were thermodynamically assessed by using CALPHAD (Calculation of Phase Diagrams) method on the basis of the presently determined experimental data. A consistent set of thermodynamic parameters has been derived for describing the Gibbs free energies of each solution phase and intermetallic compound in the Mg–Pb and Mg–Pb–Zn systems. The calculated phase diagrams and thermodynamic properties in the Mg–Pb and Mg–Pb–Zn systems are in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Sn-Zn-Sb ternary system at 400 and 500 °C were experimentally determined by electron probe microanalyzer, x-ray diffraction and differential scanning calorimetry. In this study, the ternary compound of (Zn,Sn)Sb is confirmed at 400 and 500 °C. Additionally, a liquid phase region is found at 400 °C with composition ranges of 9.09-12.86 at.% Zn and 31.47-34.22 at.% Sn, which becomes a prolongation of the main liquid as the temperature is raised to 500 °C. [ABSTRACT FROM AUTHOR]

The phase equilibria of the Bi-Cu-Zn ternary system has been firstly and comprehensively investigated by electron probe microanalyzer (EPMA) with equilibrated alloys. Two isothermal sections of the Bi-Cu-Zn ternary system at 500 and 650 °C were determined. Based on the experimental data of phase equilibria, the Bi-Cu-Zn ternary system was also thermodynamically optimized using the Calculation of Phase Diagrams (CALPHAD) method. The experimental result shows that Bi is almost insoluble in the Cu-Zn binary compounds and (Cu) phase. It is found that the critical temperatures of the miscibility gaps in the Bi-Cu and Bi-Zn binary systems gradually increase with the increasing of the third element Zn or Cu additions. Moreover, the composition range of the liquid miscibility gap gradually reduces with the temperature increasing. [ABSTRACT FROM AUTHOR]

Phase equilibria of the Ni-Cr-Si ternary system at 1000 and 1100 °C have been experimentally investigated by means of electron probe microanalyzer (EPMA) and x-ray diffraction (XRD) analysis on the equilibrated alloys. In the present work, the existence of the ternary compounds of σ (CrNiSi), π (CrNiSi), τ (CrNiSi) and τ (CrNiSi), at both 1000 and 1100 °C is confirmed. The binary γ (NiSi), δ (NiSi), and CrSi phases exhibit a considerable solubility of a third element. Additionally, a liquid phase region is found at 1100 °C in the ranges of 15.5-21.3 at.% Cr and 22.1-25.1 at.% Si. [ABSTRACT FROM AUTHOR]

Abstract: A new ternary compound (Ni, Mn)2Ga was identified in Ni–Mn–Ga system by a combination of powder X-ray diffraction, differential thermal analysis and electron probe microanalysis. The (Ni, Mn)2Ga phase was determined with a Mn2Ge-type hexagonal structure, with lattice parameters of a = 4.1629(8) nm, c = 5.2983(9) nm, and unit cell volume of 0.07952(4) nm3 after refinement. The reversible phase transformation from (Ni, Mn)2Ga hexagonal structure to bcc (B2) cubic structure at high temperature was suggested by DTA measurements. The transformation peaking temperatures during heating and cooling are 834.0 °C and 815.8 °C for Mn40Ni25Ga35, 804.7 °C and 774.1 °C for Mn50Ni17Ga33, respectively. [Copyright &y& Elsevier]

Two isothermal sections of the Ni-Cr-Ta ternary system at 1200 °C and 1300 °C have been determined by using electron probe microanalysis, energy dispersive spectroscopy and differential scanning calorimeter. A Laves phase (Ni, Cr)2Ta(HT)(C14 structure) with large solid solubility stabilized by the Ni addition was determined in both two isothermal sections. The composition range of this phase was about 25.8–66.0 at.% Cr, 2.5-44.3 at.% Ni, and 24.0-40.0 at.% Ta at 1200 °C, which increased with raising temperature. The melting point of the Ni-Cr alloys decreased with the addition of Ta. No ternary compound was found in both these two isothermal sections. The present work could be significant for practical application of nickel-based alloys and future thermodynamics assessment of the Ni-Cr-Ta ternary system. [ABSTRACT FROM AUTHOR]

In this study, the isothermal sections of the Co-Re-Ta ternary system at 1100, 1200, and 1300 °C have been experimentally investigated by means of electron probe microanalysis and X-ray diffraction. The results indicated the following: (1) The solid solubilities of the λ3, (εCo, Re), χ-Re7Ta3, and bcc-(Ta) phases were large and changed very little from 1100 to 1300 °C; (2) more interestingly, the λ2 phase, with a very limited solubility of Re, was surrounded by the λ3 phase; (3) the solubility of Re for the μ-Co6Ta7 phase increased slowly from 1100 to 1300 °C. These experimental results will be useful for Co-based high-temperature alloys, especially as a supplement for thermodynamic databases. [ABSTRACT FROM AUTHOR]

Two isothermal sections of the Ni-V-Ta ternary system at 1200 °C and 1000 °C have been experimentally established using X-ray diffraction, electron probe microanalysis, energy dispersive spectroscopy, and differential scanning calorimeter with equilibrated key alloys. The equilibrium composition of each phase is measured by electron probe microanalysis and energy dispersive spectroscopy. The results indicate that: (1) nine three-phase and eight three-phase regions were confirmed in the isothermal section at 1200 °C and 1000 °C, respectively; (2) the C14 phase with a large solubility of about 51.2 at. % Ni was observed at 1200 °C, while it forms a single-phase region at 1000 °C; (3) a small liquid region was confirmed at 1200 °C, but disappeared at 1000 °C. [ABSTRACT FROM AUTHOR]

Abstract: The phase equilibria in the Co–W–Nb ternary system were experimentally investigated using optical microscopy, electron probe microanalysis and X-ray diffraction on equilibrated alloys. In this study, isothermal sections of the Co–W–Nb ternary system at 1000 °C, 1100 °C and 1200 °C were determined, and no ternary compound was found. Further results show that a Nb-stabilized Co3W phase is stable at 1100 °C, but not at 1200 °C in the Co–W–Nb system. The α Co2Nb and γ Co2Nb phases were identified to possess large solubility of W in the present study. The newly determined phase equilibria of the Co–W–Nb in the present study will provide useful information for the development of cemented carbides and high-temperature structural materials. [Copyright &y& Elsevier]

Phase equilibria of the Al-Co-Ta ternary system over the whole composition range at 1200 °C and 1300 °C were experimentally determined from the equilibrated alloys using electron probe microanalysis, scanning electron microscopy, and X-ray diffraction. The measured results indicate that, at 1200 °C, the addition of Al can stabilize the λ 1 -Co 2 Ta phase (Laves C14-type), which is absent in binary system, and forms a broad phase region parallel to the Al-Co axis in the Al-Co-Ta ternary isothermal sections. The ternary compound of the Heusler phase AlCo 2 Ta (L2 1 -type) was confirmed at both investigated isothermal sections with the composition range about 49.7–55.7 at% Co and 14.7–23.6 at% Ta. In addition, a large solubility of Al was identified in the μ-Co 6 Ta 7 phase. Based on the experimental results, the published data of the Al-Co and Al-Ta binary systems, and the reassessed Co-Ta parameters from the current work, a thermodynamic assessment of the Al-Co-Ta system was undertaken using the CALPHAD technique. A set of reliable thermodynamic parameters for the Al-Co-Ta system was obtained with a satisfactory agreement with the experimental data. The calculated liquidus projection and invariant reaction scheme in the Al-Co-Ta ternary system were presented. The present work can provide essential experimental and thermodynamic data for the establishment of the Co-based alloy database. • The isothermal sections of the Al-Co-Ta ternary system at 1200 °C and 1300 °C were experimentally determined. • The addition of Al stabilizes the λ 1 -Co 2 Ta phase (Laves C14-type) at 1200 °C. • A large solubility of Al was identified in the μ-Co 6 Ta 7 phase. • The composition range of ternary compound AlCo 2 Ta (L2 1 -type) was defined at 1200 °C and 1300 °C isothermal sections. • The Co-Ta binary and the Al-Co-Ta ternary systems were thermodynamically assessed using CALPHAD technology. [ABSTRACT FROM AUTHOR]

• The isothermal sections at 1300, 1100 and 900 °C were experimentally determined. • A new ternary compound (named F) was detected within the compositional range of Ni 23–25 Ta 39–40 Si 35–38. • The range of the ternary Laves phase (C14) was revised to be Ni 39–54 Ta 26–33 Si 13–27. • The binary NiTa 2 and Ta 2 Si phases form a continuous solid solution (Ni, Si)Ta 2. Three isothermal sections of the Ni-Ta-Si ternary system at 1300, 1100 and 900 °C were constructed in the whole composition range and analysed using electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. In addition to the known ternary G, E, H and C14 phases, a new compound with the composition of Ni 23–25 Ta 39–40 Si 35–38 was detected for the first time, herein designated as the F phase. Furthermore, the continuous (Ni, Si)Ta 2 phase was found to be stable and the composition range of the ternary C14 Laves phase was revised to be Ni 39–54 Ta 26–33 Si 13–27. The newly determined phase equilibria in the Ni-Ta-Si ternary system can be useful in guiding alloying strategies or composition design of Ni-based superalloys. [ABSTRACT FROM AUTHOR]