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Phase structure and microstructure of (Nd1-xCex)13.4Fe79.9B6.7 (x = 0.0–1.0) alloys that were prepared via the arc-melting method were studied experimentally in this work. The results reveal that (Nd1-xCex)13.4Fe79.9B6.7 alloys annealed at 1173 K for 360 h are a single (NdCe)2Fe14B phase with the tetragonal Nd2Fe14B-typed structure (space group P42/mnm). The formation of continuous (NdCe)2Fe14B solid solution phase in annealed (Nd1-xCex)13.4Fe79.9B6.7 alloys was confirmed. On the other hand, magnetic measurements exhibit that the coercivity, remanence, maximum magnetic energy product, and Curie temperature of (Nd1-xCex)13.4Fe79.9B6.7 ribbons that were fabricated by melt spinning technology decrease gradually with increasing Ce content, which results from the substitution of Nd by Ce in Nd2Fe14B phase due to inferior intrinsic magnetic properties of Ce2Fe14B phase.

Tb-Si intermetallics have been recognized as interesting magnetic and electrical materials. The addition of Cr can modify the property and broaden the application of Tb-Si intermetallic compounds. Understanding phase relations, phase stability and microstructural changes of relative systems are essential for tuning and improving performance of this type of materials. In this work, phase relationships in the Tb-Si-Cr ternary system have been studied based on phase and microstructure identification of key equilibrated alloys. Isothermal sections of this system at 1273 K and 1073 K were experimentally constructed by means of electron probe microanalysis, X-ray diffraction, and differential thermal analysis. As one of results, the ternary compound TbSi2Cr2 was confirmed to exist at both 1273 K and 1073 K. In addition, remarkable solubilities of the third element were detected in some binary compounds. The solubility of Cr in Tb2Si3-δ and TbSi at 1273 K are about 4.0 and 9.1 at%, respectively. The solubility of Cr in Tb5Si3 increases from 3.0 at% at 1273 K to 6.2 at% at 1073 K. Besides, the compound Tb2Si3-δ were determined to be stable ranging from 1098 ± 25 K to 1513 ± 10 K, based on the analysis of microstructure. Moreover, the annealing temperature dependence of micro-hardness for Tb2Si3-δ intermetallic phase was investigated by nano-indentation.

Phase relations in Zr-Ni-Sc ternary system were investigated experimentally through alloy sampling approach. Isothermal sections at 973, 1173, and 1273 K were constructed from the results of electron probe microanalysis (EPMA) and X-ray diffraction (XRD). No ternary phase has been detected in all these sections. Combining experiment and reasonable speculation, 12, 15 and 13 three-phase zones were obtained at 973, 1173 and 1273 K, respectively. Liquid region with a large composition range at 1273 K was found although its real boundary was estimated. The intermetallic compounds, Ni2Sc, NiSc and NiSc2, exhibit remarkable ternary solubility of Zr along the isoconcentration of Ni.

Phase equilibria in Al–Ni–Sc ternary system have been measured through alloy sampling. According to the results from electron probe microanalysis and X-ray diffraction techniques, isothermal sections of Al–Ni–Sc ternary system at 1173 K and 1273 K were constructed, where four new ternary phases, τ7 (Ni2Al5Sc), τ8 (Ni2Al4Sc), τ9 (NiAl2Sc3) and τ10 (NiAlSc5), were detected along with the formerly reported ternary compounds, τ1 (NiAlSc), τ2 (Ni2AlSc) and τ5 (NiAl2Sc). The existence of τ3 (Ni7Al16Sc6), τ4 (NiAl4Sc) and τ6 (Ni3Al9Sc) reported previously in the literature was not confirmed in this work. And τ1 shows large composition range at 1173 K and 1273 K.

Due to the high sensitivity of the unshielded 5d orbit to the host environment, Ce3+ has a wide-spread emission ranging from near ultraviolet to the red light region, making it a favorable choice for being UV-emitting phosphor activator and sensitizer of other co-doped lanthanide ions in luminescent materials. In present work, Ce4+→Ce3+ self-reduction phenomenon in the layered phosphate MgIn2P4O14 was observed. Noting that self-reduction ability is a valuable characteristic of new host materials, a new viewpoint underlying mechanism was put forward. Structure-, composition-, and temperature-dependence of photoluminescence of the new UV-emitting MgIn2P4O14: Cex phosphors were investigated, with the relative mechanism discussed. Moreover, the sensitization of Dy3+ by Ce3+ was observed in Ce3+/Dy3+ co-doped MgIn2P4O14 phosphors. The excitation region of Dy3+ in MgIn2P4O14: CeDy (220–460 nm) is markedly broadened compared to that of the Dy3+ single-doped phosphor (270–460 nm) on account of the Ce3+→Dy3+ energy transfer process. Present work shows that the MgIn2P4O14: CeDy phosphor can be promising phosphor using for fabrication of both light-emitting diodes (LEDs) and fluorescent lamps (FLs).

Luminescent materials were of vital importance in the display, lighting, and biomedical fields. Exploration of novel inorganic host materials and groping for novel color-tunable phosphor materials with good thermal stability is still a major challenge for the quality-improvement of FLs and LEDs. In the present work, a new magnesium indium phosphate, Mg3In4P6O24 (MIP), was successfully synthesized by conventional high-temperature solid-state reaction and was structurally characterized by powder X-ray diffraction analysis, in which magnesium and indium atoms co-occupy four metal cation sites, coordinating with adjacent oxygen atoms forming distorted MO5 and MO6 polyhedra. The VUV-UV excited luminescence properties of a series of Eu3+/Tb3+ doped MIP phosphors were investigated, with the temperature-dependence of photoluminescence and relative mechanism analyzed. Under the excitation of 254 nm, the MIP: EuxTby phosphors can generate bright color-tunable green-yellow-red light by changing the doping concentration. In addition, the color of emission can also be adjusted by altering the excitation wavelength for a very phosphor, MIP: Eu0.01Tb0.05. As an interesting discovery, the plot of integrated dominant emission intensities of Eu and Tb in phosphor MIP: Eu0.01Tb0.05 versus excitation wavelength exhibits analogical profile with the excitation spectra of Eu3+/Tb3+ single-doped MIP phosphor. Moreover, the representative phosphor MIP: Eu0.01Tb0.05 shows favorable thermal stability. Present work indicates that Mg3In4P6O24 is a promising host material for the fabrication of new phosphors.

The phase relationship of Ti-Hf-Mn system was studied by diffusion triple and equilibrated alloy methods. The isothermal sections at 1373, 1273 and 1173 K for this system were constructed by means of electron probe microanalysis (EPMA) and X-ray diffraction (XRD) for the first time. No ternary phase was found in the system at all these temperatures. Six, seven and seven three-phase equilibria regions have been determined at 1373, 1273 and 1174 K, respectively. In this ternary system, the intermetallic compounds TiMn2, HfMn2 and HfMn exhibit wide solid solution range at those three temperatures. In particular, the solution range of Ti in HfMn phase decreases with the increase of temperature, from 30.5 at% at 1173 K to 26.5 at% at 1373 K. Based on all available experimental data, the Ti-Hf-Mn system was evaluated using the CALPHAD method. The calculation results are in excellent agreement with the experimental data.

Phase equilibria in Zr-Ni-Pt ternary system have been experimentally determined through diffusion triple and alloy sampling approaches. Based on the results of Electron Probe Microanalysis (EPMA) and x-ray diffraction (XRD), isothermal sections of this system were constructed at 1073 and 1173 K. A new ternary phase denoted as Zr4(Pt,Ni)3 was detected with composition ranging from 2.5 to 29.7 at.% Ni and 40.7 to 12.7 at.% Pt at 1073 K while 2.2 to 25.1 at.% Ni and 40.9 to 17.5 at.% Pt at 1173 K, respectively. Three continuous solutions are formed between binary compounds ZrNi and ZrPt, Zr7Ni10 and Zr7Pt10, ZrNi3 and ZrPt3, and large ternary solubility of Ni in ZrPt4, and of Pt in Zr2Ni and ZrNi5, were observed.

Phase equilibria in the Ti–Zr–Ge ternary system at 1073 and 1173 K were investigated experimentally using equilibrated alloys with electron probe microanalysis and x-ray diffraction analysis. No ternary compounds were detected. Eleven and nine three-phase regions were determined in the Ti–Zr–Ge isothermal section at 1073 and 1173 K, respectively. Intermediate compounds ZrGe2, Zr5Ge4, Zr5Ge3, Ti5Ge4, and Ti5Ge3, possessing large solubility, extended along the Ge isoconcentration line, indicating remarkable substitution of Ti for Zr in the Zr–Ge compounds or of Zr for Ti in the Ti–Ge compounds. The solubility of Ti in ZrGe2 increased from 16.0 at.% at 1073 K to 19.3 at.% at 1173 K, while that of Zr in Ti5Ge3 remained nearly 41.0 at.% at both 1073 and 1173 K.

The phase equilibria of the Al-Sc-Y system at 873 K have been determined by scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction using individual alloys. Phase transition temperatures for some of the annealed samples have been measured by differential scanning calorimetry. Before establishing the thermodynamic description of the ternary system, the phase diagram of the Al-Y system was re-optimized, showing an improvement in the calculated enthalpy of formation of the compounds compared with previous assessments. Based on the experimental results of this work and the re-assessed Al-Y binary phase diagram, the thermodynamic description of the Al-Sc-Y ternary system was developed combining the first-principles calculation and the CALPHAD method. With the obtained thermodynamic parameters, the isothermal section at 873 K, the vertical sections at 9 at.% Sc and 16 at.% Y, and the liquidus projection are all calculated, which account for most of the experimental information satisfactorily.

Phase equilibria in the Ti-Co-Pt ternary system were measured through diffusion triple and alloy sampling. Based on the results from Electron Probe Microanalysis (EPMA) and X-ray diffraction (XRD) techniques, the isothermal sections of the Ti-Co-Pt system were constructed, which consist of 16 and 13 three-phased regions at 973 and 1173 K, respectively. A new ternary phase τ was detected, which contains 23.6–29.9 at% Pt at 973 K and 27.4–40.1 at% Pt at 1173 K. Furthermore, an invariant reaction between 973 and 1173 K was deduced, i.e. τ + Ti4Pt3 ↔ Ti3Pt + TiPt. By the way, the solubilities of Pt mainly substituting for Co in TiCo and TiCo3 respectively increase from 22.4 at% and 26.1 at% at 973 K to 23.8 at% and 33.1 at% at 1173 K.

Scintillating materials, as a class of luminescent materials, are highly demanded for practical use in the high-energy detection. However, the applications are often hampered by their low light yield (LY) or long decay time for many traditional scintillators. In this work, upon nitrogen anion doping, scintillation performance in layered borate Ba 3 In(B 3 O 6 ) 3 (BIB) has been excellently enhanced with high XEL intensity of ～3 times as large as that of commercial Bi 4 Ge 3 O 12 (BGO) and ultra-fast fluorescent decay time of ～1.25 ns. To shed light on origins of the intrinsic violet-blue emission, we measured the in-situ vacuum ultraviolet excited (VUV) emission spectra of N-BIB ceramic. Combined with experiments and first principles calculations, the band-gap reduction and donor-acceptor density increasing by nitrogen (N) doping is responsible for the enhancement of scintillation performance for N-doped Ba 3 In(B 3 O 6 ) 3 . Moreover, nitrogen anion doping rather than conventional cation doping is found to be also applicable to other intrinsic luminescent materials for enhancing performance.

In order to model the creep aging process of Al-Zn-Mg-Cu aluminum alloy using common temperature-related two-stage aging, a constitutive framework was proposed considering the creep strain and yield strength. The material parameters involved in the model were estimated using a simple fitting method from the experimental data. With a simple expression, this model is capable of handling stress relaxation, hardening response, and variable aging temperature in the creep aging process. It could also be implemented using finite element analysis software to simulate the creep strain, yield strength, and springback of the component. The modeling results are consistent with the creep strain curves measured under different applied stresses. The numerical simulations are compared with the applied experimental data and excellent consistency is observed between them.

Phase relations in Cu–Ti–Hf ternary system have been studied by diffusion triple technique supplemented with typical alloy sampling method. Based on results from electron-probe microscopy analysis and X-ray diffraction, isothermal sections of the Cu–Ti–Hf system at 800 and 700 °C were established, which consist of ten and nine three-phase regions, respectively. It is observed that Ti can completely substitute Hf in the CuHf2 phase, indicating formation of a continuous solid solution Cu(Ti,Hf)2. Hf can substitute about 20% Ti in the phase CuTi, while solubility of Ti in Cu10Hf7 and Cu51Hf14 phases reaches to 14 and 11 at.% at 800 °C, respectively. The Cu8Hf3 phase in existence at 800 °C was proved to be unstable at 700 °C. In addition, the elastic modulus and hardness of solid solution Cu(Ti,Hf)2 were determined by using nano-indentation techniques.

In present work, the phase equilibrium relations in the Ti-Ni-Hf ternary system, which are of great importance for the design of Ti-Ni based high temperature shape memory alloys, were investigated using diffusion triples and sixteen key equilibrated alloys. Based on the experimental results from electron-probe microscopy analysis (EPMA) and X-ray diffraction (XRD) techniques, two isothermal sections were constructed, which consist of 13 and 12 three-phase regions at 900 °C and 800 °C, respectively. Hf can substitute for Ti in TiNi and Ti 2 Ni phases increasing from 30, 62 at% at 800 °C to 36, 64 at% at 900 °C, respectively. The Hf 7 Ni 10 and Hf 9 Ni 11 phases show wide ternary composition ranges, while the solubility of Ti in HfNi 5 , Hf 2 Ni 7 , and HfNi phases are relatively limited. A new ternary phase of τ was detected for the first time, and the stoichiometry of τ phase is close to Ni:(Hf,Ti) = 11:14, with Ti substituting for Hf from ～5 at% to ～22 at%. The single-phase region of the τ phase became narrow as the decreasing of annealing temperature. Based on comparison of phase relations at 900 °C and 800 °C, it is speculated there is an invariant reaction TiNi + τ → HfNi + Ti 2 Ni at between 900 °C and 800 °C.

Through alloy sampling approach, phase equilibria in the Cu-Co-Zr ternary system have been determined. Based on the phases identified with electron probe microanalysis and x-ray diffraction, isothermal sections at both 873 and 1200 K were constructed. No ternary compound was detected. It is evident that remarkable ternary solubility occurs in almost all binary intermetallic phases at both temperatures. For instance, solubility of Co in Cu51Zr14 can be up to 17.6 and 27.5 at.% at 873 and 1200 K, respectively. Besides, continuous dissolution between CuZr and CoZr at 1200 K was observed, and the maximum content of Cu in CoZr at 873 K reaches to 42.5 at.%.

Phase relations in Ti-Cu-Pt ternary system have been studied through diffusion- triple technique combined with alloy sampling. Assisted with Electron Probe Microanalysis (EPMA) and x-ray diffraction (XRD) techniques, isothermal sections at 1073 and 973 K of this ternary system were constructed, which consist of 16 three-phased regions at 1073 and 973 K, where two ternary phases, respectively formulated as Ti(Cu,Pt)2 and Ti(Cu,Pt)3, were detected to exist stably at 1073 and 973 K. By the way, the 2 binary compounds, Ti3Pt5 and TiPt3− were found to be stable at 1073 and 973 K.

As a typical system in the family of heat-resistant aluminum alloys, the Al-Sc-Zr ternary system was thermodynamically studied by experimentation and theoretical calculation. Employing the scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction, the isothermal section at 873 K was determined with equilibrated alloys. Two stable ternary compounds Al 75 Sc 16 Zr 9 and Al 75 Sc 10 Zr 15 were newly discovered. By means of the differential scanning calorimetry, phase transformation temperatures of selected samples were obtained. In addition, the as-cast microstructure of individual alloys was observed to identify the primary crystallization phase during solidification. Based on the experimental information mentioned above, the Al-Sc-Zr system was thermodynamically optimized combining the first-principles calculation and the CALPHAD method, with the constituent binary system Sc-Zr optimized for the first time. Using the thermodynamic parameters obtained in this work, the isothermal section, vertical section and liquidus projection were all calculated and then compared with available experimental data, most of which could be accounted for satisfactorily.

Microstructure quantitatively analysis is significant for building the relationship between microstructure and properties, especially the ageing precipitation kinetics in aluminum alloys. In the present paper, a core parameter (aspect ratio) was introduced to describe the morphology change of precipitation. Aspect ratios of T 1 -plate precipitates in Al-Cu-Li-Zr alloys, S-plate precipitates in Al-Cu-Mg alloys and β -rod precipitates in Al-Mg-Si alloys were quantitatively analyzed. Results indicate that aspect ratios of precipitates increase at the early stage of ageing, then reach the peak and finally decrease slowly. The soft-impingement theory and HHC theory were introduced to model the ageing kinetics. Thermodynamics and kinetics parameters of different precipitates were also calculated in the model. Simulated results of different precipitates agree well with the experimental results.

Isothermal sections of the Ti-Co-Zr ternary system at 1073 K and 1173 K were determined using Ti-Co-Zr diffusion triples and equilibrated alloys with optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) and electron probe micro-analysis (EPMA) techniques. A unknown ternary phase with composition of ～Ti31.3Co37.9Zr30.8 was observed to be stable at both 1073 K and 1173 K. Two continuous solid solutions Co2(Ti, Zr) and Co(Ti, Zr) were formed between the binary intermediate compounds Co2Ti (c) and Co2Zr (c) as well as between the CoTi and CoZr intermediate compounds, respectively. The solubility of Zr in the CoTi2 phase was nearly 55.0 at% at both 1073 K and 1173 K, and the Co11Zr2 phase was proved to be non-existent at 1073 K and 1173 K. Liquid phase was observed at 1173 K and exists with a wide range in the Ti-Zr-rich part.

Phase relationships in the Ge-Mn-Ti ternary system have been studied through alloy samples approach. Assisted with Electron Probe Microanalysis (EPMA) and X-ray diffraction (XRD) techniques, isothermal sections at 973 K, 1073 K and 1173 K of this system were constructed and existence of 2 ternary phases, i.e. GeMnTi and Ge 2 MnTi, were confirmed. In addition, remarkable ternary solubilities in some binary compounds were detected, e.g. Ge in Mn 2 Ti and Mn in Ge 5 Ti 6 can be up to 15 at% and 50 at% at 1173 K, respectively. Furthermore, the substitution of Ti by Mn atoms in Ge 5 Ti 6 was confirmed with Rietveld refinement results of solid solutions, Ge 5 (Mn 0.30 Ti 0.70 ) 6 and Ge 5 (Mn 0.67 Ti 0.33 ) 6 .

Using first-principles calculations, site occupancy behaviors of transition elements in C15 NbCr2 Laves phase are systematically investigated. Elements Y, Sc, Zr, Hf, Cd, Ta, Ti and Ag prefer to occupy the Nb site, and elements Zn, Pt, Re, Tc, Ir, V, Os, Rh, Ru, Ni, Co, Mn, Fe and Cu favor to occupy the Cr site; whereas elements Mo, W, Pd and Au have weak site preference for Cr or Nb site. The present calculations agree well with the available experimental and previously calculated results. It was found that the site occupancy behavior of transition elements in NbCr2 is mainly affected by the radii of transition elements. The present calculations also propose the correlation between the site preference energy and radii of transition elements.

Phase relations in BaO-In2O3-B2O3 system were experimentally and theoretically studied. Firstly, phase equilibria in B2O3-rich corner at 1298 and 1323 K were measured with EPMA and XRD. Then, thermodynamic assessment was performed based on the measured phase relations in this work and from literatures by CALPHAD method using Thermo-Calc software. The intermediate phases were treated as stoichiometric compounds, and the liquid phase was described by the two-sublattice ionic liquid model (In3+, Ba2+)p(O2−, BO33−, B4O72−, B3O4.5)Q. A set of self-consistent thermodynamic parameters was obtained and the calculated phase diagrams and thermochemical properties conform well to the measurements.

Phase equilibria in Ti–Al–Mo ternary system are of fundamental importance to better acquire the phase-forming regulation of TiAl-based alloys. In this paper, phase relations in this system have been investigated with Ti–TiAl–Mo diffusion triples combined with key equilibrated alloys. Five isothermal sections of the Ti–Al–Mo ternary system at 1473, 1373, 1273, 1173, and 1073 K were experimentally determined by means of electron probe microanalysis, scanning electron microscope, and X-ray diffraction. The TiAl and TiAl3 phases show wide ternary composition ranges, while the solubility of Mo in the Ti3Al and αTi phases is relatively limited. The solubility of Al in the β(Ti, Mo) phase decreases from 49.0 at.% at 1473 K to 39.9 at.% at 1073 K while that of Ti in the AlMo3 phase decreases from 25.4 at.% at 1473 K to 20.8 at.% at 1073 K. Moreover, the ternary compound σ forms at a temperature between 1423 and 1373 K through a peritectoid reaction β(Ti, Mo) + AlMo3 → σ. A peri-eutectoid invariant reaction β(Ti, Mo) + AlMo3 → σ + TiAl3 at 1373–1273 K was further deduced and the existence of another invariant reaction β(Ti, Mo) + TiAl3 → σ + TiAl at a temperature between 1273 and 1173 K was also confirmed. The established phase equilibria of the Ti–Al–Mo ternary system may provide essential data required for the construction of reliable thermodynamic assessment of the Ti–Al–Mo system.

Quenching and partitioning (Q&P) or quenching and tempering (Q&T) process of modified ultrahigh carbon steel (UHCS, Fe–1.69C–1.38Si–1.84Mn–2.20Cr–0.54Mo–0.43Ni wt%) was investigated by means of scanning electronic microscopy (SEM) equipped with energy-dispersive spectrometry (EDS) and x-ray diffraction (XRD). Mechanical properties, including hardness and impact toughness, and wear resistance were also measured. After Q&P, high impact toughness (10.5 J/cm2) and wear resistance at 100 N load in dry sliding were achieved on tested samples. We attributed the optimum mechanical properties and high wear resistance to better microstructure consisting of carbon-depleted martensite, uniformly distributed fine carbides, and high volume fraction of retained austenite.

Isothermal sections at 900, 950 and 1000 °C relating to the borate Ba 3 InB 9 O 18 at BO 1.5 -rich corner in the BO 1.5 –BaO–InO 1.5 system were measured with EPMA and XRD, especially the thermal stability of Ba 3 InB 9 O 18 was studied through melting and quenching method. Results showed that isothermal section at 900 °C contains six two-phase regions and six three-phase regions, while isothermal section at 950 and 1000 °C contains three two-phase regions and three three-phase regions. In addition, Ba 3 InB 9 O 18 melts incongruently into InBO 3 and liquid at ∼1025 °C. Breaking of Ba–O bounds in Ba 3 InB 9 O 18 is the trigger of phase transition. Based on the established isothermal sections, primary crystal region of Ba 3 InB 9 O 18 was determined, which will be benefit to designing composition and process for crystal growth of scintillating material Ba 3 InB 9 O 18 .

The phase formation of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 (x = 0.10, 0.15, and 0.20; hereafter defined as Pr20Ce10, Pr15Ce15 and Pr10Ce20, respectively) and (Nd0.60Pr0.40−yCey)2.28Fe13.58B1.14 (y = 0.10, 0.20, and 0.30; hereafter defined as Pr30Ce10, Pr20Ce20 and Pr10Ce30, respectively) alloys that were prepared via the arc-melting method was investigated experimentally. The x-ray diffraction results revealed that all alloys annealed at 1173 K for 360 h consisted of a (NdPrCe)2Fe14B main phase with a tetragonal Nd2Fe14B-typed structure (space group P42/mnm) and an α-Fe minor phase, except for the Pr10Ce30 alloy, which contained an additional CeFe2 phase. The magnetic properties of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 and (Nd0.60Pr0.40−yCey)2.28Fe13.58B1.14 ribbons that were prepared by melt spinning were examined. The remanence (Br) and maximum magnetic energy product ((BH)max) of the (Nd0.70Pr0.30−xCex)2.28Fe13.58B1.14 ribbons increased first and then decreased, whereas the coercivity (Hcj) of the ribbons increased with an increase in Ce content. The Br and (BH)max of the (Nd0.60Pr0.60−yCey)2.28Fe13.58B1.14 ribbons increased, whereas the Hcj of the ribbons decreased gradually with an increase in Ce content. This changed behavior of magnetic properties is attributed to the variation of volume fraction of the α-Fe phase and different phase formations in the melt-spun ribbons. The Curie temperatures (Tc) of all ribbons decreased slightly with Ce substitution, which results from the lower Curie temperatures of Pr2Fe14B and Ce2Fe14B. The Pr10Ce30 ribbon with a higher Ce content exhibited optimal magnetic properties (Br = 9.71 kGs, Hcj = 13.09 kOe, (BH)max = 18.78 MGOe), which indicates that suitable magnetic properties of the Nd–Pr–Ce–Fe–B melt-spun ribbons can be achieved by alloy-composition and phase-formation design.

Based on diffusion triple and equilibrated alloy methods, phase relations in the Ti–Fe-Hf ternary system were investigated using the experimental data obtained through the combination of optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron probe microanalysis (EPMA) techniques. Isothermal sections of the Ti–Fe-Hf system at both 1073 K and 1273 K were well constructed. There are three and four three-phase regions in these two sections, respectively. According to the present results, Hf can dissolve into FeTi at approximately 3.0% at both 1073 K and 1273 K. A continuous solid solution of Fe2(Ti, Hf) forms between the binary intermediate compounds Fe2Ti and Fe2Hf (h). Fe2Hf(c) and FeHf2 show large solid solubilities. The solubility of Ti in Fe2Hf(c) changes from 33.9% at 1073 K to 39.0% at 1273 K, while that of FeHf2 can reach up to approximately 63.0% at 1273 K. No ternary compound exists in the Ti–Fe-Hf ternary system.

The experimentally measured diffusion coefficients of fcc Cu-Fe and Cu-Ti alloys in the published literature were reviewed critically in the present work. On the basis of the available thermodynamic information, the atomic mobilities of Cu, Fe, and Ti in fcc Cu-Fe and Cu-Ti alloys as a function of temperature and composition were assessed in terms of the CALPHAD method using the DICTRA® software. The optimized mobility parameters are presented. The calculated diffusion coefficients show an excellent agreement with the experimental data. The composition-distance profiles of the Cu-Ti binary diffusion couples reported in the literature were also predicted using the assessed mobility parameters. Overall good agreement is achieved between the experimental results and simulations.

Novel CaInBO4: xEu(3+) phosphors were synthesized by solid-state reaction method. Their luminescent properties were characterized mainly by UV-visible PLE, PL, VUV, Decay lifetime, and TG-DTA. The excitation and emission spectra indicate that these phosphors can be effectively excited by ultraviolet about similar to 254 nm and exhibit red emission centered at similar to 613 nm attributed to D-5(0)-> F-7(2) transition of Eu3+. Optimum Eu3+ concentration of this phosphor is around 9 mol%. The effect of Al3+/Gd3+ and Ba2+/Sr2+ co-doped CaInBO4: Eu phosphor have been investigated, and the concentration dependence of the emission intensity shows that the optimum doping concentrations of Al3+ and Ba2+ are 3 mol% and 6 mol %, respectively. The UV-vis diffuse reflectance spectra indicate that these phosphors have wide transparent region and the incorporation of Al3+ ions and Ba2+ ions is in favor of light absorption for CIBO: Eu phosphor. The band gaps for these samples were obtained from diffuse reflection spectra, and the excitation wavelengths of phosphors were modified by adjusting their band gaps. According to their decay curves, the calculated lifetime of (Ca1-z, Ba/Sr-z) (In1-x-y, Al/Gd-y) BO4: xEu(3+) phosphors are all shorter than 2 ms. The chromaticity diagram shows that these phosphors can emit red light. The TG-DTA data presents that these phosphors have good thermal stability below 1100 degrees C. The present work suggests that these novel phosphors have potential applications for fluorescent lamps. (C) 2015 Elsevier B.V. All rights reserved.

Ruthenium addition was found to be beneficial in inhibiting the formation of the detrimental topologically closed-packed (TCP) phases in Ni-based single crystal superalloys; thus, the Ni–Cr–Ru phase stability is very valuable for better understanding of the constitutional effects of Ru in multicomponent Ni-base superalloys. Four isothermal sections of the Ni–Cr–Ru system at 800 °C, 900 °C, 1000 °C and 1200 °C were constructed from results obtained from diffusion multiples using scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The measured phase equilibria together with prior experimental results were used to optimize a CALPHAD thermodynamic description of the Ni–Cr–Ru ternary system using thermodynamic parameters of the Ni–Cr and Ni–Ru systems published in the literature and modified Cr–Ru parameters from the current study. The intermetallic compound sigma phase in the Cr–Ru system was described with a simplified two-sublattice model, (Cr,Ru) 20 (Cr,Ru) 10 , by taking into account future extension of the model into higher order systems. Comparison between the calculated results and the experimental measurements was made to demonstrate the reliability of the current thermodynamic parameters for the Ni–Cr–Ru system. For easy implementation of the thermodynamic parameters into some existing thermodynamic databases, a version of the thermodynamic description of the Ni–Cr–Ru system with an older sublattice model, (Cr,Ni,Ru) 10 (Cr) 4 (Cr,Ni,Ru) 16 , for the sigma phase was also developed.

Phase equilibria in the Cu–Ni–Zr ternary system have been measured through alloy sampling combined with diffusion couple approach. According to the phase relations identified with electron probe microanalysis and X-ray diffraction techniques, isothermal sections at both 1073 and 1293 K were constructed. It is evident that remarkable ternary solubility occurs in almost all binary intermetallic phases at both temperatures. The formerly reported ternary compounds T1 (Cu20–40Ni40–60Zr20) and T2 (Cu20–25Ni60–65Zr15) were not verified in this work. No other ternary compound was detected. In addition, continuous dissolution between Cu10Zr7 and Ni10Zr7 at 1073 K was observed.

The Al–Dy–Zr ternary system has been experimentally studied and thermodynamically assessed to contribute to the development of novel heat-resistant aluminum alloys. Using equilibrated alloys, the isothermal section of this ternary system at 873 K has been established by means of scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). Experimental information on vertical sections was obtained by performing differential scanning calorimetry (DSC) analysis on selected annealed samples and that on liquidus projection was extracted from the as-cast samples by observing the primary crystallization phases. In addition, the first-principles method was employed to calculate the enthalpy of formation of metastable compounds involved in the sublattice model. Based on the experimental data and first-principles calculation results in this work, the Al–Dy–Zr system was optimized within the framework of the calculation of phase diagram (CALPHAD) method. Good agreement was found between the experimental data and the thermodynamic calculation results, which indicates that the thermodynamic description developed in this work is reliable.

The Zr–Al–Gd system, as a key constituent ternary in Cu-, Gd- and Zr-based bulk metallic glasses, was thermodynamically studied in this work. Employing equilibrated alloys, the isothermal section at 873 K was established by means of scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction. Phase transformation temperatures were determined by performing differential scanning calorimetry analysis on selected samples. Moreover, the microstructure of the as-cast samples was observed to identify primary solidification phases. Based on all experimental information of this work, the Zr–Al–Gd system was thermodynamically optimized with the assistance of the first-principles calculation. The calculated isothermal section, vertical sections and liquidus projection account for experimental observations satisfactorily.

Phase equilibria in the Fe–Sn–Ti ternary system at 1073 and 1273 K were experimentally investigated through alloy sampling approach facilitated with electron probe micro-analyzer and X-ray diffraction. Two ternary compounds TiFe 2 Sn and Ti 2 FeSn were detected. Ten 3-phase equilibria at 1073 K, including β(Ti)+Ti 3 Sn+FeTi, Ti 3 Sn+FeTi+Ti 5 Sn 3 , FeTi+Ti 5 Sn 3 +Ti 2 FeSn, Ti 2 FeSn+Fe 2 Ti+TiFe 2 Sn, Ti 2 FeSn+Ti 5 Sn 3 +Ti 6 Sn 5 , FeTi+Fe 2 Ti+Ti 2 FeSn, Ti 2 FeSn+Ti 6 Sn 5 +TiFe 2 Sn, TiFe 2 Sn+Ti 6 Sn 5 +Liquid, TiFe 2 Sn+Fe 5 Sn 3 +Liquid and α(Fe)+Fe 2 Ti+TiFe 2 Sn, and seven 3-phase equilibria including β(Ti)+Ti 3 Sn+FeTi, Ti 3 Sn+FeTi+Ti 5 Sn 3 , Ti 3 Sn+Ti 2 Sn+Ti 5 Sn 3 , FeTi+Fe 2 Ti+Ti 5 Sn 3 , Fe 2 Ti+Ti 2 FeSn+Ti 5 Sn 3 , Ti 2 FeSn+Fe 2 Ti+TiFe 2 Sn and Ti 2 FeSn+Ti 6 Sn 5 +TiFe 2 Sn at 1273 K were experimentally confirmed. At 1073 K, the homogeneity ranges of Ti 2 FeSn were 45.5–51.4 at% Ti and 24–27.7 at.% Sn while TiFe 2 Sn exhibited a large homogeneity range of 46.9–66.4 at% Fe and 22.7–26.4 at% Sn, the solubility of Sn in Fe 2 Ti,Fe in Ti 5 Sn 3 , Ti in Fe 5 Sn 3 and Fe in Ti 6 Sn 5 can be up to 4.6 at.%, 10.2 at%, 3.7 at% and 21 at%, respectively, while at 1273 K, Solubility of Sn in Fe 2 Ti considerably increased to 10.8 at%, Fe in Ti 5 Sn 3 changes little. According to the measured phase relations, an invariant reaction was further deduced, which was Fe 2 Ti+Ti 5 Sn 3 ↔FeTi+Ti 2 FeSn occurring between 1073 K and 1123 K.

Phase relations of Ti-Mn-Zr ternary system at 1020 and 800 °C have been investigated mainly by metallographic observations, x-ray diffraction and electron microprobe analysis.A new ternary compound named K was detected, which shows a remarkable homogeneity range both at 1020 and 800 °C. The isothermal section at 1020 °C contains 8 single-phase regions, 13 two-phase regions and 6 three-phase regions, while the isothermal section at 800 °C consists of 9 single-phase regions, 15 two-phase regions and 7 three-phase regions. The continuous solid solution (Ti,Zr)Mn2 shows a wide homogeneous range both at 1020 and 800 °C, and the phase TiMn4 exists at 1020 °C and disappears at 800 °C.

Subsolidus phase equilibrium of CoO–In 2 O 3 –B 2 O 3 system has been investigated mainly by solid-state reaction and powder X-ray diffraction method. A novel compound Co 2 InBO 5 was found and synthesized for the first time. There are five definite three-phase regions and one solid solution Co 3 − X In X BO 5 (0 X ⩽ 1) in this system under present experimental conditions. This new compound Co 2 InBO 5 and high temperature metastable phase Co 3 BO 5 can form continuous solid solution at all relative concentrations. Crystal structure of three representative Co 3− X In X BO 5 solid solution compounds ( X = 0.4, 0.7, and 1) were refined and determined from X-ray powder diffraction data using Rietveld method. The results showed that the Co 3− X In X BO 5 (0 X ⩽ 1) solid solution crystallized in the orthorhombic space group Pbam (No. 55) with the ludwigite structure type. The lattice parameters ( a , b and c ) of these solid solution compounds increase linearly when In replace Co atom gradually (i.e. with the increase of the value of X ), which obeys the Vegard’s rule. The trigonal BO 3 group in these Co 3− X In X BO 5 solid solution compounds was confirmed by their infrared absorption spectra.

Both Al–Gd and Gd–Zr binary systems were re-assessed using the CALPHAD (calculation of phase diagram) method to ensure a multi-component system containing them can be accurately described. Compared with previous assessments, the features of this work are reflected from the following aspects. Firstly, the C15_laves phase Al2Gd was treated as an intermetallic compound with a negligible homogeneity range using the two-sublattice model (Al, Gd)2(Al, Gd), meanwhile the liquid phase being described with the substitutional solution model. Secondly, first-principles calculations were carried out to provide theoretical information for optimization. The enthalpies of mixing of Gd1−xZrx (x = 0.25, 0.5, 0.75) hcp_A3 solid solutions were calculated by applying the Special Quasirandom Structure containing 16 atoms (SQS_16). Finally, the inverse liquid miscibility appearing at high temperatures in previous studies was reduced for the Al–Gd system and eliminated for the Gd–Zr system. The calculated results for both binary systems reproduce the experimental and theoretical data satisfactorily, evidencing the reliability of the thermodynamic descriptions established in this work.

Phase equilibria in Al–Ti–Zr ternary system at 1273 K were experimentally investigated through alloy sampling combined with electron probe micro-analyzer (EPMA) and X-ray diffraction (XRD). No ternary compound was detected. Experimental results show that there is a continuous solid solution β(Ti, Zr) which dissolves up to 25.5 at.% Al, and Ti can substitute Zr in most Al–Zr binary intermediate phases to a certain degree while the maximum solubility of Zr in α 2 (Ti 3 Al) and γ(TiAl) reaches up to 25 at.% and 9 at.%, respectively. The isothermal section consists of 16 single-phase regions, 26 two-phase regions and 14 three-phase regions.

Phase diagram of Co–Ge binary system was thermodynamically assessed by using CALPHAD approach in this study. The excess Gibbs energy of the solution phases, liquid, α(Co) and ɛ(Co), were modeled with Redlich–Kister polynomial. Magnetic contribution to the Gibbs energy was also taken into account for α(Co) and ɛ(Co). Considering its crystal structure and solubility range, the intermetallic compound βCo5Ge3, with B82-structure, was particularly described with a three-sublattice model, (Co,Va)1:(Co)4:(Co,Ge)3. And the compound CoGe was described with two-sublattice model according to its crystal structure. Other intermetallic compounds were described as stoichiometric phases because of their narrow homogeneity ranges or unknown crystal structure. In order to obtain a reasonable description of several Co–Ge compounds, first-principle calculations were performed before optimization to determine their formation enthalpies. Finally, a set of thermodynamic parameters was finally obtained so that most data of phase boundaries and thermodynamic properties of various phases were reproduced in present optimization.

Phase relations of Al-Ni-Zr ternary system were investigated with more than 60 ternary alloy compositions combining with x-ray diffraction, scanning electron microscopy equipped with energy dispersive spectroscopy and electron probe microanalysis. The isothermal section at 850 °C for x(Al)

The Cu–Fe–Ti ternary system has been systematically studied through experimental investigation and thermodynamic modeling. Combining diffusion multiple technique with selected equilibrated alloys, equilibrium phase relations in the Cu–Fe–Ti system at 800 °C have been established by means of SEM/EDS (Scanning Electron Microscopy/Energy Dispersive Spectrum) and EPMA (Electron Probe Micro-Analysis). DSC (Differential Scanning Calorimetry) analysis has been also employed to measure phase transformation temperatures in order to construct various vertical sections of the Cu–Fe–Ti system. Liquidus projection of the ternary system has been determined by identifying primary crystallization phases in as-cast alloys. Based on all available experimental information from literatures and this work, the Cu–Fe–Ti ternary system was modeled with the aid of the CALPHAD (CALculation of PHAse Diagram) method. Comprehensive comparisons made between experimental and calculated results shed light on reliability of the current thermodynamic description.

Based on the thermodynamic description, experimental diffusion coefficients and empirical relations, the atomic mobilities of Al and Zr in fcc_Al, bcc_Zr and hcp_Zr phases have been optimized. From the comparisons between the calculated and measured diffusion coefficients, it can be seen that most of the experimental data are reproduced well. A good prediction was also made in the composition–distance profile of the diffusion zone in the Zr/Zr-2.8 wt% Al diffusion couple. Introducing the concept of “average interdiffusion coefficient”, the growth of ZrAl 3 intermetallic phase with a narrow homogeneity range in Zr/Al diffusion couples was simulated using the obtained atomic mobility parameters. Meanwhile the average interdiffusion coefficients were assessed and their temperature dependence was then established. The difference in the average interdiffusion coefficients of the ZrAl 3 phase based on separate experiments was also explained.

Subsolidus phase equilibrium of BaO-In2O3-B2O3 system has been investigated mainly by solid-state reaction technique and powder X-ray diffraction method. There are 15 definite three-phase regions under present experimental conditions. Two ternary compounds, Ba3InB9O18 and Ba3InB3O9 were found and confirmed in this system. Crystal structure of Ba3InB3O9 was determined from X-ray powder diffraction data using Rietveld method. It crystallizes in space group R (3) over bar with six formula units of a cell with a = 12.7713(4)angstrom, c=9.3950(2)angstrom and V = 1327.09(8)angstrom(3). Coordination surrounding of B-O in this structure, [BO3](3-) group, was confirmed by infrared absorption spectrum of Ba3InB3O9. Ba3In1-xTbxB3O9 (x = 0.1-0.5) phosphors exhibited green emission at about 543 nm with 370 nm light excited. There is neither emission from D-5(3) level nor concentration quenching observed in the case of Ba3InB3O9:Tb3+, which can be explained from the crystal structural features of the matrix Ba3InB3O9. Chemical stabilization, simple preparation, and luminescence characteristics make phosphors Ba3InB3O9:Tb3+ have potential applications in white light-emitting diodes. (C) 2011 Elsevier B.V. All rights reserved.

The phase equilibria in the Mg-rich corner of Mg–Zn–Gd ternary system at 673 K were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), and electron probe microanalysis (EPMA). Three ternary phases, X-(Mg12ZnGd), W-(Mg3Zn3Gd2) and I-(Mg3Zn6Gd1), have been identified, which are in equilibrium with Mg solid solution. A thermodynamic modeling and optimization of Zn–Gd and Mg–Zn–Gd systems has been carried out for the first time using the CALPHAD method. The sublattice model was used to describe the thermodynamic functions of both solution phases and intermetallic phases presented in these systems. In particular, order/disorder transition between BCC_B2 and BCC_A2 has been taken into account, and their Gibbs energies were expressed with identical function. The thermodynamic database was applied to case studies of experimentally observed microstructures and demonstrated that it is a valuable basis for alloy design.

The Au–Ga binary system was assessed thermodynamically using the CALPHAD method through Thermo-calc ® software based on the critical review of the available experimental data from the published literature. The solution phases including liquid, fcc(Au), D0 24 and orthorhombic(Ga) are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich–Kister polynomial. The intermetallic compounds, β - Au 7 Ga 2 , β ′ - Au 7 Ga 2 , γ - Au 7 Ga 3 , AuGa and AuGa 2 are treated as stoichiometric compounds. A set of self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Au–Ga binary system can be used to reproduce well the reported phase equilibria and thermodynamic properties data.

A thermodynamic description of the Mg–Nd–Zn system was developed by means of the CALPHAD (CALculation of PHAse Diagrams) method. The constituent binary systems Mg–Nd and Nd–Zn were re-optimized based on the experimental phase equilibria and thermodynamic properties available in the literature. Combining with the thermodynamic parameters of the Mg–Zn system cited from the reference, the Mg–Nd–Zn ternary system was evaluated. The Gibbs energies of the solution phases (liquid, BCC_A2, DHCP, HCP_A3 and HCP_Zn) were described by the subregular solution model with the Redlich–Kister polynomial function, and those of the stoichiometric compounds, Nd2Zn17, NdZn11_H, NdZn11_L, Nd3Zn22, Nd13Zn58, Nd3Zn11, NdZn3, NdZn2 and Mg2Nd, were described by the sublattice model. The compounds Mg3Nd and Mg41Nd5 in the Mg–Nd–Zn system were treated as the formulae (Mg, Zn)3(Mg, Nd) and (Mg, Nd, Zn)41(Mg, Nd)5. The order–disorder transition between BCC_B2 and BCC_A2 phases was treated using a two-sublattice model (Mg, Nd, Zn)0.5(Mg, Nd, Zn)0.5. Based on experimental data, four stable ternary compounds τ1(Mg7Nd1Zn12), τ2(Mg7Nd2Zn11), τ3(Mg6Nd1Zn3) and τ4(Mg6Nd3Zn11) were taken into consideration in this system. A set of self-consistent thermodynamic parameters of the Mg–Nd–Zn system was obtained. Projection of the liquidus surface, selected vertical and isothermal sections were calculated using the proposed thermodynamic description. Comprehensive comparisons between the calculated and measured phase diagrams show that almost all the accurate experimental information is satisfactorily accounted for by the present thermodynamic description.