The Ternary System Nickel/Silicon/Titanium Revisited
Frank Cui2010, Zeitschrift Fur Anorganische Und Allgemeine Chemie
Sign up for access to the world's latest research
checkGet notified about relevant papers
checkSave papers to use in your research
checkJoin the discussion with peers
checkTrack your impact
Abstract
The constitution of the ternary system Ni/Si/Ti is investigated over the entire composition range using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), differential thermal analysis (DTA), and metallography. The solid state phase equilibria are determined for 900 °C. Eight ternary phases are found to be stable. The crystal structures for the phases τ1NiSiTi, τ2Ni4Si7Ti4, τ3Ni40Si31Ti13, τ4Ni17Si7Ti6, and τ5Ni3SiTi2 are corroborated. For the remaining phases the compositions are determined as Ni6Si41Ti53 (τ6), Ni16Si42Ti42(τ7), and Ni12Si45Ti43 (τ8). The reaction scheme linking the solid state equilibria with the liquidus surface is amended to account for these newly observed phases. The discrepancies between previous experimental conclusions and modeling results are addressed. The liquidus surface is dominated by the primary crystallisation field of τ1NiSiTi, the only congruently melting phase.
Related papers
The ternary system Al–Ni–Ti Part II: thermodynamic assessment and experimental investigation of polythermal phase equilibria
Intermetallics, 1999
The Al±Ni±Ti phase diagram has been thermodynamically assessed and a consistent set of thermodynamic functions has been developed. The thermodynamic modeling is based on an experimental investigation of the phase equilibria in the composition range of 0.14x Al 40.7. Alloys were prepared by argon-arc or vacuum-electron beam melting of elemental powder blends. X-ray powder diraction, metallography, SEM and EMPA-techniques were employed to analyze the samples in the as-cast state as well as after annealing at 800, 900 and 1000 C. The existence of the four ternary compounds, (1 to (4 , has been con®rmed, although homogeneity regions dier signi®cantly from reports in the literature. The homogeneous phase, previously claimed at ``Al 23 Ni 26 Ti 51 '', is shown by high resolution microprobe and X-ray diraction measurements to be an extremely ®ne-grained eutectic structure. The congruent melting behavior of (4 elxi 2 i is con®rmed, but, in contrast to earlier reports, primary crystallization and congruent melting have been observed for (1 el 13 xi 2 i 5 and (3 el 3 xii 2. In contrast to earlier assessments, (1 Y(2 and (3 are experimentally found to be stable at 800, 900 and 1000 C. The thermodynamic modeling of the ternary phases (2 and (3 is done with sim-pli®ed sublattice models, considering their crystal structure and homogeneity ranges. The sublattice model for (4 is taken from an earlier asessment of the nickel-rich ternary phase equilibria. The present assessment covers the entire composition range. An application to the solidi®cation behavior of ternary alloys is also exempli®ed.
The ternary system Al–Ni–Ti Part I: Isothermal section at 900°C; Experimental investigation and thermodynamic calculation
Intermetallics, 1999
Phase relations in the ternary system Al±Ni±Ti have been experimentally established for the isothermal section at 900 C for concentrations 0.1 4 x Al 4 0.7. The investigation is based on X-ray powder diraction, metallography, SEM and EMPA-techniques on about 40 ternary alloys, prepared by argon-arc or vacuum-electron beam melting of proper elemental powder blends. The existence of four ternary compounds, t 1 to t 4 , is con®rmed, however, in contrast to earlier investigations at signi®cantly dierent compositions and with dierent shape of the homogeneity regions. This is particularly true for the phase regions of t 3-Al 3 NiTi 2 with the MgZn 2-type structure ranging from Al 30 Ni 28 Ti 42 (composition lowest in Al) to Al 50 Ni 16 Ti 34 (composition richest in Al) and for t 2-Al 2 NiTi. The complex atom site substitution mechanism in t 3 changing from Ti/Al exchange at Al-poor compositions towards Ni/Al replacement for the Al-rich part was monitored in detail by quantitative X-ray powder diraction techniques (Rietveld analyses). In contrast to earlier reports, claiming a two-phase region Ni{Al x Ti 1-x } 2 +t 3 , we observed two closely adjoining three-phase equilibria: a 2-AlTi 3 +Ni{Al x Ti 1-x } 2 + t 4-AlNi 2 Ti and a 2-AlTi 3 +t 3-Al 2 NiTi 2 +t 4-AlNi 2 Ti. The earlier reported ``homogeneous phase at Al 23 Ni 26 Ti 51 H '' was shown by high resolution microprobe and X-ray diraction measurements to be an extremely ®negrained eutectic. The experimental results are in ®ne agreement with the thermodynamic calculation.
Experimental Investigations of the Isothermal Sections for the Ni-Si-Zr Ternary System at 1023 and 1173 K
Journal of Phase Equilibria and Diffusion, 2020
Phase equilibria in the Ni-Si-Zr ternary system have been investigated experimentally by means of x-ray diffraction and electron probe micro-analyzer on equilibrated ternary alloys. Four ternary phases were detected at 1023 and 1173 K. The Ni 16 Si 7 Zr 6 phase tends to present in two different contrasts and has a wide homogeneity range. The reported Ni 2 Si 9 Zr 14 phase is not detected in this work. It is proposed that the Ni 2 Si 9 Zr 14 phase is unstable at these temperatures. As for the binary phases, Ni 5 Zr and Ni 7 Zr 2 dissolve appreciable amounts of Si and cNi 31 Si 12 , bNi 3 Si, dNi 2 Si, NiSi 2 exhibit a considerable solubility of Zr.
Experimental Investigation in the Quaternary Systems Ti–Ni–Al–N and Ti–Ni–Al–O
Journal of Solid State Chemistry, 2000
The experimental evaluation of phase equilibria in the Ti+Ni+Al+N and Ti+Ni+Al+O phase diagrams are based on alloy samples, which were prepared of elemental powder blends by argon-levitation melting in a Hukin crucible. The experimental investigation employed X-ray powder di4raction, metallography, SEM, and EMPA techniques in the as-cast state as well as after annealing at 9003C. Two quaternary compounds Ti 3 NiAl 2 N and Ti 3 NiAl 2 O deriving from the 5lled Ti 2 Ni type (phase) were observed. The novel phases are in equilibrium with the Ti 2 Ni-type solid solution phase (Ti 1؊x Al x) 2 Ni, which exhibits a maximum solubility of 14 at.% Al in binary Ti 2 Ni. Atom order in all these phases was monitored by quantitative X-ray powder di4raction (Rietveld analyses). The di4erence of X-ray spectra among the various phases deriving from parent Ti 2 Ni type was analyzed and the complex atom site occupation mode was discussed in terms of the general classi5cation scheme for phases.
Evidence of an ordered ternary phase in the section Ni–Ti5Sn3 of the ternary Ti–Ni–Sn: Crystal structure and phase stability
Solid State Sciences, 2020
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Distributed under a Creative Commons Attribution-NonCommercial| 4.0 International License
Electronic structure and phase stability study in the Ni-Ti system
Physical Review B, 1995
We present the results of a phase stability study in the Ni-Ti system. In particular, the formation energies of the three NiTi2, NiTi, and Ni3Ti compounds have been calculated using the full potential linear-muffin-tinorbital method. The correlation between the electronic concentration and the crystal structure is interpreted in terms of the filling of bonding states for the Ni3Ti compound. Two sets of effective cluster interactions are determined allowing us to include bccand fcc-based solid solutions in the phase stability analysis. Ordering effects are treated by means of the cluster variation method. An attempt to calculate the compositiontemperature phase diagram of the Ni-Ti system is proposed.
On the Quaternary System Ti-Fe-Ni-Al
Journal of Phase Equilibria and Diffusion, 2008
The homogeneity ranges of the Laves phases and phase relations concerning the Laves phases in the quaternary system Ti-Fe-Ni-Al at 900°C were defined by x-ray powder diffraction (XPD) data and electron probe microanalysis (EPMA). Although at higher temperatures the Laves phase forms a continuous solid solution, two separate homogeneity fields of TiFe 2-based (denoted by k Fe) and Ti(TiNiAl) 2-based (denoted by k Ni) Laves phases appear at 900°C. The relative locations of Laves phases, G phase, Heusler phase, and CsCl-type phase as well as the associated tie-tetrahedra were experimentally established in the quaternary for 900°C and presented in three-dimensional (3D) view. Furthermore, a partial isothermal section TiFe 2-TiAl 2-TiNi 2 was constructed, and a connectivity scheme, derived for equilibria involving Laves phases in the Ti-Fe-Ni-Al quaternary system at 900°C was derived. As a characteristic feature of the quaternary phase diagram, the solid solubility of fourth elements in both the TiFe 2-based and Ti(NiAl) 2-based Laves phases is limited at 900°C and is dependent on the ternary Laves phase composition. A maximum solubility of about 8 at.% Ni is reached for composition Ti 33.3 Fe 33.3 Al 33.4. Structural details have been evaluated from powder x-ray and neutron diffraction data for (i) the Ti-Fe-Ni ternary and the Ti-Fe-Ni-Al quaternary Laves phases (MgZn 2-type, space group: P6 3 /mmc) and (ii) the quaternary G phase. Atom site occupation behavior for all phases from the quaternary system corresponds to that of the ternary systems. For the quaternary Laves phase, Ti occupies the 4f site and additional Ti (for compositions higher than 33.3 at.%Ti) preferably enters the 6h site. Aluminum and (Fe,Ni) share the 6h and the 2a sites. The compositional dependence of unit cell dimensions, atomic coordinates, and interatomic distances for the Laves phases from the quaternary system is discussed. For the quaternary cubic G phase, a centrosymmetric as well as a noncentrosymmetric variety was observed depending on the composition: from combined x-ray and neutron powder diffraction measurements Ti 33.33 Fe 13.33 Ni 10.67 Al 42.67 was found to adopt the lower symmetry with space groupF " 43m.
Thermodynamic assessment of the Ni–Te system
Journal of Materials Science
A thermodynamic assessment of the Ni-Te system has been performed using the Calphad method, based on experimental data available in the literature. The proposed description has been developed for use in the modeling of fissionproduct-induced internal corrosion of stainless steel cladding in Generation IV nuclear reactors. DFT calculations were performed to obtain 0 K properties of solid phases to assist the thermodynamic optimization. The ionic liquid twosublattice model was used, and most solution phases were modeled using interstitial metal sub-lattices. With a strict number of parameters, the resulting description satisfactorily reproduces all thermodynamic properties and hightemperature phase transitions. The metastable miscibility gap in the Ni-rich liquid that is experimentally suggested is not present in the final description. The d phase exhibits a metastable order-disorder transition between the CdI 2 and NiAs types of interstitial nickel distribution. The CdI 2 prototype is the stable space group at room temperature. Low-temperature ordering phase transitions have been disregarded in this description, since they are not of interest to the application of corrosion in nuclear reactors.
Isothermal Sections of the Ni-Cr-Ta Ternary System at 1200 °C and 1300 °C
Metals, 2019
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.
Phase relations in the Nd–Al–Si system at 500°C
Journal of Alloys and Compounds, 2001
The partial isothermal section of the phase diagram of the Nd-Al-Si ternary system at 5008C (50 at.% Nd or less) has been investigated by X-ray diffraction analysis, differential thermal analysis, scanning electron microscopy and electron micro-probe analysis. The existence of six binary compounds, aNd Si , bNdSi (x < 1.8 < 2.0), NdAl, NdAl , NdAl and aNd Al , and three ternary 2 3 x 2 3 3 1 1 compounds, NdAl Si (g ), NdAl Si (d ), NdAl Si (h), was confirmed. The ternary compound NdAl Si was not found in 2 2 1.75 0.25 1.25 0.25 1.5 0.5 this section. This isothermal section consists of 11 single-phase regions, 21 two-phase regions and 11 three-phase regions. The compound NdAl Si has a large homogeneity range, while the other ternary compounds are non-solubility compounds.
Phase equilibria and phase transformations in the Ti-rich corner of the Fe–Ni–Ti system
Intermetallics, 2006
While the main features of the Fe-Ni-Ti system are well known at low Ti content, literature review of the Ti-rich corner revealed inconsistencies between experimental reports. This investigation presents new experimental results, defined to remove the uncertainties concerning melting behavior and solid-state phase equilibria of the (Ni,Fe)Ti 2 phase with the adjacent (Fe,Ni)Ti (B2, CsCl-type structure) and β-Ti (A2, W-type) phases. Six samples have been prepared and examined by differential thermal analysis performed in yttria and alumina crucibles, and by scanning electron microscopy in the as-cast state as well as equilibrated at 900 °C.
Solid state phase equilibria in the ternary Nd–Si–B system at 1270K
Journal of Alloys and Compounds, 2006
The solid state phase equilibria in the ternary Nd-Si-B diagram were determined at 1270 K using experimental techniques such as X-ray diffraction, scanning electron microscopy and electron probe microanalysis. No ternary compounds were obtained in the phase diagram with the exception of the interstitial Nowotny phase Nd 5 Si 3 B x. The characteristic feature of this diagram is the major role played by the neodymium tetraboride NdB 4 , which is in thermodynamic equilibrium with all the binary silicides. The binary systems Nd-Si and Nd-B were re-investigated prior to the study of the ternary one. X-ray single crystal structures of Nd 2 B 5 (Pr 2 B 5-type), NdB 4 (ThB 4-type), Nd 5 Si 3 (Cr 5 B 3-type) and Nd 5 Si 4 (in both types Zr 5 Si 4 and Sm 5 Ge 4) were solved. For the first time, Nd 5 Si 4 has been found to adopt the Sm 5 Ge 4type. Structural relationships between NdB 4 , Nd 2 B 5 and Gd 2 B 5 on one side and between both forms of Nd 5 Si 4 on the other side are largely discussed.
Experimental study of the Fe–Ni–Ti system
Intermetallics, 2010
In this investigation phase relations in the Fe-Ni-Ti system were studied and two isothermal sections at 800 C and 1000 C as well as a revised liquidus projection were established. Microstructural characterisation of the as-cast alloys and of samples equilibrated at 800 and 1000 C was performed by scanning electron microscopy (SEM), chemical compositions of the phases were analysed by electron probe microanalysis (EPMA), and liquidus temperatures were examined by differential thermal analysis (DTA). The experimental results clarify some uncertainties concerning the melting behaviour and the solid-state phase equilibria between the phases (Ni,Fe)Ti 2 , (Fe,Ni)Ti and b-Ti. The present data also confirm that the solid solubility of Ti in g-(Fe,Ni) varies in dependence on the Fe:Ni ratio and decreases with decreasing temperature. The liquidus projection as well as the reaction scheme in the Ti-lean part are modified because two ternaries eutectic E 1 : L4 g-(Fe,Ni) þ Fe 2 Ti þ Ni 3 Ti and E 2 : L 4 Fe 2 Ti þ Ni 3 Ti þ (Fe,Ni)Ti are found at 1108 and 1099 C, respectively. Intermetallics j o u r n a l h o m e pa g e : w w w . e l s e v i e r . c o m / l o c a t e / i n t e r m e t 0966-9795/$ -see front matter Ó
Thermodynamic modelling of the Nb–Ni–Si phase diagram based on the 1073 K isothermal section using ab initio calculationsNi–Si phase diagram CALPHAD Ab initio calculations Thermodynamic model Assessment
Recent binary thermodynamic descriptions are used as a starting point for the modelling of the ternary Nb–Ni–Si phase diagram. First-principles electronic structure calculations, within the framework of the Density Functional Theory (DFT), are performed for the determination of formation energies of known ternary compounds. The results are introduced into a CALPHAD-type thermodynamic model using the Compound Energy Formalism (CEF). The model parameters are then optimised in order to match the experimental 1073 K isothermal section of the ternary phase diagram.
An Electron and X-Ray Diffraction Investigation of Ni1+xTe2 and Ni1+xSe2CdI2/NiAs Type Solid Solution Phases
Journal of Solid State Chemistry, 2001
The reported wide-range nonstoichiometric Ni 1؉x Te 2 , 04 4 x4 40.83, and Ni 1؉x Se 2 , 0.574 4x4 40.92, CdI 2 /NiAs structure type solid solution 5elds have been carefully reinvestigated via electron and X-ray powder di4raction to search for evidence of Ni/vacancy ordering and superstructure phases. In the case of telluride, evidence is thereby found for a Ni 3 Te 4 superstructure phase attempting to condense out at x&0.5 while, in the case of selenide, three quite distinct phases have been identi5ed within the Ni 1؉x Se 2 solid solution 5eld. An intriguing characteristic honeycomb di4use-intensity distribution has also been observed across the solid solution 5eld in the case of the Ni 1؉x Te 2 system. Its presence has been attributed to low frequency phonon modes along certain very speci5c directions of reciprocal space.
Phase diagram investigations of the Ni–Sn–Bi system
Journal of Alloys and Compounds, 2009
Phase equilibria were studied in the system Ni-Sn-Bi at 733 and 903 K. For this purpose, 30 ternary samples were synthesized using intimately mixed powders. After annealing in quartz ampoules and quenching, all alloys were analysed by scanning electron microscope. Differential thermal analyses (DTA) were done with specimens having chemical compositions near to the expected ternary Bi-Sn eutectic point.
Phase equilibria in the Ni-Al-Ti system at 1173 k
Metallurgical Transactions A, 1985
Phase stabilities of self-organized nc-TiN/a-Si3N4 nanocomposites and of Ti1−xSixNy solid solutions studied by ab initio calculation and thermodynamic modeling
Thin Solid Films, 2008
Bulk properties of stable binary fcc-TiN and hcp(β)-Si 3 N 4 , hypothetical fcc-SiN and hcp(β)-Ti 3 N 4 , and ternary Ti 1 − x Si x N y phases are calculated by ab initio method. The values of total energies are then used for thermodynamic calculations of the lattice instabilities of hypothetical binary phases of fcc-SiN and hcp-Ti 3 N 4 , and of the interaction parameters of ternary Ti 1 − x Si x N y phases. Based on these data, Gibbs free energy diagrams of the quasi-binary TiN y-SiN y system are constructed in order to study the relative phase stability of the metastable ternary fcc-and hcp-Ti 1 − x Si x N y phases over the entire range of compositions. The results are supported by the published data from chemical and physical vapor deposition experiments. The constructed Gibbs free energy diagram and phase selection diagram of quasi-binary TiN y-SiN y system in fcc structure show that metastable fcc-Ti 1 − x Si x N coatings should undergo chemically spinodal decomposition into coherent fcc-TiN and fcc-SiN. Due to a high lattice mismatch between fcc-TiN and hcp-Si 3 N 4 , and to much higher lattice instability of fcc-SiN with respect to stable hcp-Si 3 N 4 , only about one monolayer of pseudomorphic SiN y interfacial phase is stable.
Experimental and Calculated Ti-rich Corner of the Al-Si-Ti Ternary Phase Diagram
The phase equilibria between S(bcc), a(hcp), Ti,Al-ar(hcp) and TigSi,(hcp) in the Ti-Al-Si system have been investigated in the temperature range of 700 to 1200°C. Isothermal sections of the ternary phase diagram have been assessed employing thermodynamic software, which uses the compound-energy model to describe mathematically the phase. Available experimental phase equilibria results on the Ti-Al-Si system were used to calculate missing binary and ternary interaction parameters and assess isothermal phase diagrams. Extrapolations in the resulting tie-triangles indicate the existence of three eutectoid reactions in the Ti-rich comer of the ternary diagram: B->a+Ti& a->ar+Ti,Si, and E-zar+Ti,Si,. Additionally, extrapolations in the pta,+a tie-triangle observed at 1100°C indicate that two possibilities arise to represent a peritectoid reaction involving a, E and a2 phases: p+a,->a and P+a-x2, depending on the alloy composition and on the effect of temperature on the solubility of Si in a phase. 0
Related topics
Loading Preview
Sorry, preview is currently unavailable. You can download the paper by clicking the button above.