Binary Alloy Phase Diagrams Research Articles

Observing Tin–Lead Alloys by Scanning Electron Microscopy: A Physical Chemistry Experiment Investigating Macro-Level Behaviors and Micro-Level Structures

Scanning electron microscopy (SEM) was introduced into undergraduate physical chemistry laboratory curriculum to help students observe the phase composition and morphology characteristics of tin–lead alloys and thus further their understanding of binary alloy phase diagrams. The students were captivated by this visual analysis method, which allowed them to more fully consider the relationship between macroscopic behaviors and microscopic structures of materials. During this process, the abilities of critical thinking were inspired, and a spirit of team work came into being.

Supplemental Literature Review of Binary Phase Diagrams: Bi-Ga, Bi-Y, Ca-H, Cd-Fe, Cd-Mn, Cr-La, Ge-Ru, H-Li, Mn-Sr, Ni-Sr, Sm-Sn, and Sr-Ti

Binary Alloy Phase Diagrams, 2nd edition, a comprehensive collection of alloy phase diagrams for 2159 binary systems, was published in 1990 (T.B. Massalski, H. Okamoto, P.R. Subramanian, and L. Kacprzak., ASM International, Materials Park, OH [Massalski2]). This review intends to provide more recent information on the binary phase diagrams for the Bi-Ga, Bi-Y, Ca-H, Cd-Fe, Cd-Mn, Cr-La, Ge-Ru, H-Li, Mn-Sr, Ni-Sr, Sm-Sn, and Sr-Ti systems that have become available after 1990. The criteria for selecting such information for inclusion in this review are (1) systems for which no phase diagram was given in [Massalski2], (2) complete diagrams that are substantially different from the earlier version, and (3) partial diagrams that alter or clarify the earlier version. Thermodynamic consistency of the new phase diagrams was checked based on phase rules and the diagrams were modified if necessary. However, each updated phase diagram has not gone through the ordinary evaluation process. Accordingly, a newer phase diagram is not always a better diagram, especially when there is too little published data on a system. For convenience, reaction tables and crystal structure data have been added when new information was available.

Phase diagram calculation and predication of Au–Pd–Zr ternary system

Au–Pd–Zr ternary alloy phase diagram at 25 °C was calculated by Panda phase calculation software, and the thermodynamic data were based on three binary alloy phase diagrams: Pd–Au, Au–Zr, and Pd–Zr. Five composition points in the ternary phase diagram were selected to predict the precipitation order. One (32Au–32Pd–36Zr) of the five composition points in ternary phase diagram was chosen to verify the correctness of the phase diagram calculation and the precipitation order by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The unknown phase in XRD patterns was predicated by EDS and materials studio (MS) software. The experimental results show that there are seven key ternary reactions points and 17 phase regions in all isothermal sections at 25 °C. The thermodynamic process and microstructure for the alloy phase can be described in order according to the vertical section in phase diagram. The phase compositions of the chosen one point are consistent with calculation prediction. The unknown phase in XRD patterns should be Zr2AuPd by the first principle X-ray simulation.

Supplemental Literature Review of Binary Phase Diagrams: Al-Mg, Bi-Sr, Ce-Cu, Co-Nd, Cu-Nd, Dy-Pb, Fe-Nb, Nd-Pb, Pb-Pr, Pb-Tb, Pd-Sb, and Si-W

Binary Alloy Phase Diagrams, 2nd edition, a comprehensive collection of alloy phase diagrams for 2159 binary systems, was published in 1990 (T.B. Massalski, H. Okamoto, P.R. Subramanian, and L. Kacprzak., ASM International, Materials Park, OH [Massalski2]). This review intends to provide more recent information on the binary phase diagrams for the Al-Mg, Bi-Sr, Ce-Cu, Co-Nd, Cu-Nd, Dy-Pb, Fe-Nb, Nd-Pb, Pb-Pr, Pb-Tb, Pd-Sb, and SiW systems that have become available after 1990. The criteria for selecting such information for inclusion in this review are (1) systems for which no phase diagram was given in [Massalski2], (2) complete diagrams that are substantially different from the earlier version, and (3) partial diagrams that alter or clarify the earlier version. Thermodynamic consistency of the new phase diagrams was checked based on phase rules and the diagrams were modified if necessary. However, each updated phase diagram has not gone through the ordinary evaluation process. Accordingly, a newer phase diagram is not always a better diagram, especially when there is too little published data on a system. For convenience, reaction tables and crystal structure data have been added when new information was available.

Supplemental Literature Review of Binary Phase Diagrams: Ag-Nd, Ag-Zr, Al-Nb, B-Re, B-Si, In-Pt, Ir-Y, Na-Si, Na-Zn, Nb-P, Nd-Pt, and Th-Zr

Binary Alloy Phase Diagrams, 2nd edition, a comprehensive collection of alloy phase diagrams for 2159 binary systems, was published in 1990 (T.B. Massalski, H. Okamoto, P.R. Subramanian, and L. Kacprzak., ASM International, Materials Park, OH [Massalski2]). This review intends to provide more recent information on the binary phase diagrams for the Ag-Nd, Ag-Zr, Al-Nb, B-Re, B-Si, In-Pt, Ir-Y, Na-Si, Na-Zn, Nb-P, Nd-Pt, and Th-Zr systems that have become available after 1990. The criteria for selecting such information for inclusion in this review are (1) systems for which no phase diagram was given in [Massalski2], (2) complete diagrams that are substantially different from the earlier version, and (3) partial diagrams that alter or clarify the earlier version. Thermodynamic consistency of the new phase diagrams was checked based on phase rules and the diagrams were modified if necessary. However, each updated phase diagram has not gone through the ordinary evaluation process. Accordingly, a newer phase diagram is not always a better diagram, especially when there is too little published data on a system. For convenience, reaction tables and crystal structure data have been added when new information was available.

Supplemental Literature Review of Binary Phase Diagrams: Al-Bi, Al-Dy, Al-Gd, Al-Tb, C-Mn, Co-Ga, Cr-Hf, Cr-Na, Er-H, Er-Zr, H-Zr, and Ni-Pb

Binary Alloy Phase Diagrams, 2nd edition, a comprehensive collection of alloy phase diagrams for 2159 binary systems, was published in 1990 (T.B. Massalski, H. Okamoto, P.R. Subramanian, and L. Kacprzak., ASM International, Materials Park, OH [Massalski2]). This review intends to provide more recent information on the binary phase diagrams for the Al-Bi, Al-Dy, Al-Gd, Al-Tb, C-Mn, Co-Ga, Cr-Hf, Cr-Na, Er-H, Er-Zr, H-Zr, and Ni-Pb systems that have become available after 1990. The criteria for selecting such information for inclusion in this review are (1) systems for which no phase diagram was given in [Massalski2], (2) complete diagrams that are substantially different from the earlier version, and (3) partial diagrams that alter or clarify the earlier version. Thermodynamic consistency of the new phase diagrams was checked based on phase rules and the diagrams were modified if necessary. However, each updated phase diagram has not gone through the ordinary evaluation process. Accordingly, a newer phase diagram is not always a better diagram, especially when there is too little published data on a system. For convenience, reaction tables and crystal structure data have been added when new information was available.

Study on Influencing Factors of Mechanical Properties of Ti(C,N)-Based Cermets

Ti(C,N)-based cermets were fabricated by the vacuum hot-processing technique. The effect of sintering process, initial powder size and binder content on mechanical properties of Ti(C,N)-based cermets were investigated. The composite was analyzed by the observation of scanning electron microscope (SEM) and energy dispersive spectrometry (EDS). The results showed that a lower sintering temperature led to insufficient liquid-phase sintering process, which reduced the density of the composite. However, higher temperature and longer holding time resulted in abnormal grain growth, which was not good for improving the mechanical properties of the composite. With the refinement of the initial powder size of the Ti(C,N), the fracture toughness reduced slightly, the flexural strength and Vickers hardness increased. The better mechanical properties were obtained when the binder content of the cermets was designed based on the eutectic composition of Mo-Ni binary alloy phase diagram.

Supplemental Literature Review of Binary Phase Diagrams: Ag-Ni, Al-Cu, Al-Sc, C-Cr, Cr-Ir, Cu-Sc, Eu-Pb, H-V, Hf-Sn, Lu-Pb, Sb-Yb, and Sn-Y

Binary Alloy Phase Diagrams, 2nd edition, a comprehensive collection of alloy phase diagrams for 2159 binary systems, was published in 1990 (T.B. Massalski, H. Okamoto, P.R. Subramanian, and L. Kacprzak., ASM International, Materials Park, OH [Massalski2]). This review intends to provide more recent information on the binary phase diagrams for the Ag-Ni, Al-Cu, Al-Sc, C-Cr, Cr-Ir, Cu-Sc, Eu-Pb, H-V, Hf-Sn, Lu-Pb, Sb-Yb, and Sn-Y systems that have become available after 1990. The criteria for selecting such information for inclusion in this review are (1) systems for which no phase diagram was given in [Massalski2], (2) complete diagrams that are substantially different from the earlier version, and (3) partial diagrams that alter or clarify the earlier version. Thermodynamic consistency of the new phase diagrams was checked based on phase rules and the diagrams were modified if necessary. However, each updated phase diagram has not gone through the ordinary evaluation process. Accordingly, a newer phase diagram is not always a better diagram, especially when there is too little published data on a system. For convenience, reaction tables and crystal structure data have been added when new information was available.

Supplemental Literature Review of Binary Phase Diagrams: Cd-Se, Cu-Hg, Cu-Ho, Eu-Mg, H-Sr, Hf-Si, La-Mn, Mn-Nd, Nb-Y, Ni-Y, Pb-Se, and Sc-Sr

Recent literature on Cd-Se, Cu-Hg, Cu-Ho, Eu-Mg, H-Sr, Hf-Si, La-Mn, Mn-Nd, Nb-Y, Ni-Y, Pb-Se, and Sc-Sr phase diagrams is reviewed in this article in order to update the 1990 compilation Binary Alloy Phase Diagrams, 2nd edition, by T.B. Massalski, et al. For some systems reaction tables and crystal structure data have been included, as well. Diagrams have been checked for consistency with rules for phase diagram construction and modified when necessary. In addition, diagrams needing more work have been identified.

A theory of spinodal decomposition stabilized by coherent strain in binary alloys

A phenomenological theory is developed which predicts the possible existence of meta-stable chemical composition modulations in the spinodal (instable) region of the phase diagram of binary alloys. This is accomplished through a modified elastic energy term in the theory of diffuse interfaces by Cahn and Hilliard: Analogously to Cahn’s expansion of the molar chemical free energy, also the (un-relaxed) internal stress tensor due to chemical composition modulations is expanded in a Taylor series of the spatial derivatives of the local composition up to second order terms. This mathematical approach is confirmed by atomistic modeling.

Supplemental Literature Review of Binary Phase Diagrams: Bi-Ce, Bi-Er, C-Ce, C-La, C-Pr, Cd-I, Cr-Cu, Cu-Er, Er-Sb, F-Sm, F-Yb, and Fe-Gd

Recent literature on Bi-Ce, Bi-Er, C-Ce, C-La, C-Pr, Cd-I, Cr-Cu, Cu-Er, Er-Sb, F-Sm, F-Yb, and Fe-Gd phase diagrams is reviewed in this article in order to update the 1990 compilation Binary Alloy Phase Diagrams, 2nd edition, by T.B. Massalski, et al. For some systems reaction tables and crystal structure data have been included, as well. Diagrams have been checked for consistency with rules for phase diagram construction and modified when necessary. In addition, diagrams needing more work have been identified.

Supplemental Literature Review of Binary Phase Diagrams: Cs-In, Cs-K, Cs-Rb, Eu-In, Ho-Mn, K-Rb, Li-Mg, Mg-Nd, Mg-Zn, Mn-Sm, O-Sb, and Si-Sr

Recent literature on Cs-In, Cs-K, Cs-Rb, Eu-In, Ho-Mn, K-Rb, Li-Mg, Mg-Nd, Mg-Zn, Mn-Sm, O-Sb, and Si-Sr phase diagrams is reviewed in this article in order to update the 1990 compilation Binary Alloy Phase Diagrams, 2nd edition, by T.B. Massalski, et al. For some systems reaction tables and crystal structure data have been included, as well. Diagrams have been checked for consistency with rules for phase diagram construction and modified when necessary. In addition, diagrams needing more work have been identified.

Full-Potential KKR Calculations for Point Defect Energies in Fe-Based Dilute Alloys, Based on the Generalized-Gradient Approximation

We present systematically ab-initio calculations for defect energies of 3d and 4sp impurities (Sc­Ge) in Fe. The calculations are based on the Generalized-Gradient-Approximation in the density-functional formalism and the full-potential Korringa-Kohn-Rostoker (FPKKR) Green’s function method. First we examine the distance dependence, from the 1st- to the 10th-neighbors, of the impurity-impurity (I­I; I = Sc­Ge) interaction energies (Eint) and show that for most cases, the 1st-neighboring I­I interaction energies (E 1) are dominant. We found that fundamental features of phase diagrams of Fe-based binary alloys, such as segregation, solid solution and order, known experimentally, may be classified by use of the sign and magnitude of E 1. Second we discuss the calculated results for the 1st- and 2nd-neighboring interaction energies of 3d and 4sp impurities with perturbed-angular-correlation (PAC)-probe Sn in Fe. The comparison of the calculated results with available experimental results shows that the observed attraction for Sn­Co, Sn­Ni and Sn­Cu may be understood by the 1st-neighboring interaction energies of these impurity pairs, while the obsreved repulsion for Sn­Ga, and Sn­Ge by the 2nd-neighboring interaction energies of these impurity pairs. We also discuss the magnetism of single impurities X (= Sc­Cu) in Fe. The anti-parallel coupling to the bulk magnetization of the neighboring Fe atoms is stable for Sc­Mn, while the parallel coupling for Fe­Cu. [doi:10.2320/matertrans.M2013176]

Моделирование термических кривых охлаждения в процессе упорядочения сплавов стехиометрии AB, A3B и A3B5 в приближении жесткой кристаллической решетки

An algorithm of calculation of thermal cooling curves and ordering kinetics during monotonous decrease of temperature of a stoichiometric binary alloy is offered. The algorithm is based on the assumptions of rigid crystal lattice and pairwise interatomic potentials. As an example of application of this algorithm the AB, A3B, and A3B5 alloys based of the square lattice are considered taking into account atomic interactions up to the second coordination sphere. The developed algorithm can be used for modeling certain elements of binary alloy phase diagrams. <br />

A1-L12 interfacial free energies from data on coarsening in five binary Ni alloys, informed by thermodynamic phase diagram assessments

The data on coarsening of γ′-type precipitates (Ni3X, with the L12 crystal structure) in Ni–Al, Ni–Ga, Ni–Ge, Ni–Si, and Ni–Ti alloys are re-evaluated in the context of recent (TIDC) and classical (LSW) theories of coarsening, with the objective of ascertaining the best values possible of interfacial free energies, σ, of the γ/γ′ interfaces in these five alloy systems. The re-evaluations include fitting of the particle size distributions, reanalyzing all the available data on the kinetics of particle growth and kinetics of solute depletion, and using thermodynamic assessments of the binary alloy phase diagrams to calculate curvatures of the Gibbs free energies of mixing. The product of the work is two sets of interfacial free energies, one set for the analysis using the recent TIDC theory and the other for the analysis using the classical LSW theory. The TIDC-based analysis yields lower values of σ by about a factor of 2/3. All the interfacial energies are considerably larger, by factors ranging from ~4 to 10, than those previously reported, which were for the most part calculated from data on coarsening assuming ideal-solution thermodynamics. In the TIDC theory the width of the interface, δ, is allowed to increase with particle size, r. A simple equation relating σ to the ratio of the gradient energy and δ is used to show that σ can remain constant even though δ increases with r. Published work supporting this contention is presented and discussed.

Surface segregation and adsorption effects of iron–technetium alloys from first-principles

Surface properties of Tc-rich and Fe-rich portions of the Tc–Fe binary alloy phase diagram were computed in this work on the basis of density functional theory. Tc and Fe were found to have minimal degrees of mixing in the parent phases, consistent with the experimentally derived phase diagram. The influence of oxygen on surface phase stability was also studied, with no significant impact on surface segregation or degree of surface mixing. Oxygen adsorption was shown to change the ordering of surface facets in Tc, such that the pyramidal phase becomes lower in energy than the prismatic phase, even with low coverage of oxygen. No evidence for increased surface segregation upon oxidation was found for the solid-solution phases. A potential–pH surface Pourbaix diagram was derived for Tc and H, OH and O adsorbed sub-monolayers were shown to be precursors to oxide formation. While Tc and Fe have similar reactivities and properties in their parent phases, and hence, also in solid-solution, the properties of the intermetallic are expected to be significantly different due to the size-mismatch between the elements.

Thermodynamic Assessment of V-Rare Earth Systems

Vanadium is a refractory metal with high melting point (1910 °C) that has good structural strength, good room-temperature corrosion resistance, and low thermal neutron-absorption cross section. Vanadium is primarily used as a steel additive to improve the strength of steels by forming stable nitrides and carbides. Addition of yttrium to vanadium alloys can improve the oxidation resistance and mechanical properties. In this work, three binary systems, V-Ce, V-La, and V-Y, were thermodynamically assessed based on the ASM Binary Alloy Phase Diagrams using CALPHAD approach. Self-consistent thermodynamic descriptions for all three systems were obtained.

Prediction of Phase Diagrams in Nano-Sized Binary Alloys

The authors have evaluated the surface properties as well as phase diagrams of alloys on the basis of thermodynamic databases. Extending these techniques, we developed a new system to estimate phase equilibria of metals and alloys in small particle systems. The present paper describes our trial to evaluate the phase diagrams of binary alloys in nano-sized particle systems through thermodynamic databases.

Boron Particle Composite Plating with Ni–B Alloy Matrix

Ni–B alloy films containing amorphous boron particles (referred to as “Ni–B alloy composite films”) were fabricated by electrodeposition and were subsequently subjected to heat-treatment. Their compositions and microstructures were characterized, and their hardness was evaluated. The content of boron particles in the alloy composite films increased with boron particle concentration in the plating baths. In addition, the total boron content in the films increased with decreasing current density, reaching a maximum value of 34.3 atom %. The boron particles were homogeneously distributed in these alloy composite films and exhibited no cohesion. Heat-treatment of the alloy composite films consisting of a Ni–B alloy matrix and the boron particles led to a phase conversion from an inhomogeneous amorphous phase to stable homogeneous crystalline phases, which were similar to those in the Ni–B binary alloy phase diagram. The hardness of the Ni–B alloy 34.3 atom % B composite film was higher than that of a Ni–B alloy film both before and after heat-treatment.

Isothermal Phase Diagrams of Binary Alloys and Two Oxidants

An example of an isothermal thermodynamic phase diagram of a quaternary system composed of a binary alloy and two oxidants has been calculated under appropriate values of the stability of the corresponding compounds, assuming that each metal forms only one compound with each oxidant. Initially, two-dimensional sections of the complete three-dimensional diagram made along planes corresponding to constant values of one of the variables involved were examined in detail. The actual structure of this type of three-dimensional diagram was then discussed by analyzing the shape and the boundaries of the various regions corresponding to the conditions of stability of each phase taken separately or in combination with other phases.