Thermodynamic Assessment of the Fe-Y System

ＴｈｅｒｍｏｄｙｎａｍｉｃＡｓｅｓｍｅｎｔｏｆｔｈｅＦｅＹＳｙｓｔｅｍＤｕＺｈｅｎｍｉｎ，ＺｈａｎｇＷｅｉｊｉｎｇ（杜振民）（张维敬）ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙＢｅｉｊｉｎｇ，Ｂｅｉｊｉｎｇ１０００８３，Ｃｈ...     

Thermodynamic Assessment of Co-Y System

ＴｈｅｒｍｏｄｙｎａｍｉｃＡｓｓｅｓｓｍｅｎｔｏｆＣｏ－ＹＳｙｓｔｅｍＤｕＺｈｅｎｍｉｎ；ＺｈａｎｇＷｅｉｊｉｎｇａｎｄＺｈａｏＬｉａｎｇ（杜振民）（张维敬）（赵亮）（ＤｅｐｏｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎ...     

Thermodynamic Assessment of Fe-Dy System

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅａｌｏｙｓｙｓｔｅｍｓｏｒｉｎｔｅｒｍｅｔａｌｉｃｃｏｍｐｏｕｎｄｓｃｏｍｐｏｓｅｄｏｆ３ｄｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓａｎｄｒａｒｅｅａｒｔｈｓｈａｖｅａｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎａｓａｃｌａ...     

Thermodynamic Assessment of Dy-Co System

ＴｈｅｒｍｏｄｙｎａｍｉｃＡｓｓｅｓｓｍｅｎｔｏｆＤｙ－ＣｏＳｙｓｔｅｍＳｕＸｕｐｉｎｇ；ＺｈａｎｇＷｅｉｊｉｎｇａｎｄＤｕＺｈｅｎｍｉｎ（苏旭平）（张维敬）（杜振民）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ...     

Thermodynamic Assessment of Gd-Ni System

ＴｈｅｒｍｏｄｙｎａｍｉｃＡｓｓｅｓｓｍｅｎｔｏｆＧｄ－ＮｉＳｙｓｔｅｍＳｕＸｕｐｉｎｇ；ＺｈａｎｇＷｅｉｊｉｎｇａｎｄＤｕＺｈｅｎｍｉｎ（苏旭平）（张维敬）（杜振民）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ...     

Assessment and Prediction of Thermodynamic Functions of Compounds in Sialon System

According to the quasi-paraboloid rule, a computer program was developed and the Gibbs free energy functions of some compounds in Sialon system were assessed and predicted. It makes the theoretical design of the Sialon materials possible.     

Experimental Investigation of the Phase Equilibria in the Co–V–Sn Ternary System

The phase equilibria of the Co–V–Sn ternary system at the 900 and 1000 °C sections were investigated experimentally by means of electron probe microanalysis and x-ray diffraction analysis. Seven three-phase regions were found in the isothermal section at 900 °C and six triphase regions at 1000 °C. The Heusler-type ternary compound Co₂VSn was confirmed at 900 °C in the composition ranges of 36.7–57.6 at.% Co and 11.8–20.9 at.% Sn, becoming slightly wider at the higher temperature of 1000 °C. Sn dissolves in α(Co), Co₃V, and σ-Co₂V₃ phases with low solubility. V is almost insoluble in liquid, with solubility of less than 0.5 at.%. The solubility of Co in V₃Sn phase increased with temperature, from 4.4 at.% at 900 °C to 11.6 at.% at 1000 °C.     

Experimental Investigation of Phase Equilibria in the Cu–Mo–Ti Ternary System

Phase equilibria of the Cu–Mo–Ti ternary system at 800 and 900 °C have been experimentally investigated using electron probe microanalysis and x-ray diffraction analysis. A ternary intermetallic compound (τ phase) was newly found, exhibiting a homogeneity range at both 800 and 900 °C. Furthermore, the nominal as-cast alloys Cu₅₀Mo₁₀Ti₄₀, Cu₃₀Mo₃₀Ti₄₀, Cu₁₅Mo₅₀Ti₃₅, Cu₄₀Mo₃₀Ti₃₀, Cu₁₅Mo₂₀Ti₆₅, Cu₁₅Mo₃₀Ti₅₅, Cu₁₅Mo₂₅Ti₆₀, Cu₄₀Mo₁₀Ti₅₀, and Cu₆₀Mo₅Ti₃₅ presented a common separated microscopic morphology because of the ternary extent of the Cu–Mo binary liquid phase separation. The newly determined phase equilibria may provide essential information to support thermodynamic assessment and development of Cu–Mo-based alloys.     

Experimental and Thermodynamic Analysis on Phase Equilibria of Ni-rich Region in Ni-Al-Ti System

1ＩｎｔｒｏｄｕｃｔｉｏｎＮｉｂａｓｅｓｕｐｅｒａｌｌｏｙｓｈａｖｅｃｏｍｐｌｅｘｍｉｃｒｏｓｔｒｕｃｔｕｒｅｓｃｏｎｓｉｓｔｉｎｇｏｆγａｎｄγ′(ｃｏｍｐｏｎｅｎｔｉｓＮｉ3Ａｌ,ｓｔｒｕｃｔｕｒｅＬｌ2)ａｓｍａｊｏｒｐｈａｓｅｓａｎｄｔｈｅｃａｒｂｉｄｅｓａｎｄｂｏｒｉｄｅｓａｓｍｉｎｏｒｐｈａｓｅｔｅｎｄｉｎｇｔｏｐｏｐｕｌａｔｅｔｈｅｇｒａｉｎｂｏｕｎｄａｒｉｅｓ[1～3].Ｂｅｓｉｄｅｓｔｈｅｓｅｐｈａｓｅｓ,ｕｎｄｅｓｉｒａｂｌｅｃｏｍｐｏｕｎｄｓｓｕｃｈａｓη,μ,σａｎｄＬａｖｅｓｃａｎａ…     

Experimental Investigation of Phase Equilibria in Ti–Zr–Ge System

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.     

Phase Equilibria Calculation of the Ga-In-Sb Ternary System

ＰｈａｓｅＥｑｕｉｌｉｂｒｉａＣａｌｃｕｌａｔｉｏｎｏｆｔｈｅＧａＩｎＳｂＴｅｒｎａｒｙＳｙｓｔｅｍＸｉｅＹｕｎ′ａｎ，ＱｉａｏＺｈｉｙｕ，ＸｉｎｇＸｉａｎｒａｎａｎｄＷａｎｇＣｏｎｇ（谢允安）（乔芝郁）（邢献然）（王聪）Ｄｅｐｔ．ｏｆＰｈｙｓ...     

Phase Equilibria of the Al-Rich Corner in the Al-Cu-Fe-Si System at 650 °C

Phase equilibria in the isothermal section of the Al-Cu-Fe-Si quaternary system with Al being fixed at 85 at.% and the related ternary subsystems at 650 °C have been investigated by scanning electron microcopy coupled with energy dispersive spectroscopy and x-ray diffraction. Two four-phase regions are identified in the isothermal section of the Al-Cu-Fe-Si quaternary system. Three three-phase regions and two three-phase regions are found in Al-rich corner of Al-Fe-Si and Al-Cu-Fe, respectively, and the Al-rich corner of the Al-Cu-Si system contains only the liquid phase. No new ternary and quaternary compounds are found in the present work.     

Phase Equilibria of the Al–Zn–Bi–Fe Quaternary System at 600 °C

Isothermal sections of the Al–Zn–Bi–Fe quaternary system at 600 °C with fixed Al content of 75 at.% and fixed Zn content of 50 at.% were determined by scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy and x-ray powder diffraction analysis. One four-phase region and four four-phase regions were identified in the 75 at.% Al and 50 at.% Zn sections, respectively. The Bi-poor L₁ phase and Bi-rich L₂ phase are in equilibrium with (Al), FeAl₃, Fe₂Al₅, α-Fe, and δ, respectively. No new quaternary phase was found in these two sections. Bi is almost insoluble in all Fe–Al and Fe–Zn compounds.     

Phase Equilibria in the Al-Zr-Nd System at 773 K

The isothermal section of the phase diagram of the Al-Zr-Nd ternary system at 773 K has been investigated by means of x-ray powder diffraction (XRD), scanning electron microscopy (SEM) and optical microscopy (OM) for the first time. The existences of 14 binary compounds i.e. Al₃Zr, Al₂Zr, Al₃Zr₂, AlZr, Al₃Zr₄, Al₂Zr₃, AlZr₂, AlZr₃, α-Al₁₁Nd₃, Al₃Nd, Al₂Nd, AlNd, AlNd₂ and AlNd₃ were confirmed. The isothermal section consists of 17 single-phase regions, 31 binary-phase regions and 15 ternary-phase regions. No binary compound is found in the Nd-Zr binary system. No ternary compound is found in the present work. None of the phases in this system reveals a remarkable solid solution at 773 K.     

Thermodynamic Description of Ni-Co-Gd System

ＴｈｅｒｍｏｄｙｎａｍｉｃＤｅｓｃｒｉｐｔｉｏｎｏｆＮｉＣｏＧｄＳｙｓｔｅｍ①ＳｕＸｕｐｉｎｇ，ＺｈａｎｇＷｅｉｊｉｎｇａｎｄＤｕＺｈｅｎｍｉｎ（苏旭平）（张维敬）（杜振民）ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎ...     

Thermodynamic investigations in the solid state of the lanthanum–magnesium–zinc system

The La–Mg–Zn phase diagram is experimentally investigated at 595 K, x_La > 4% and the corresponding isothermal section is partially determined. This section includes 5 substitutional solid solutions based on the binary compounds (LaMg, LaZn, LaMg₃, LaMg_10.3 and La₂Zn₁₇) and three ternary phase (La₈(Mg,Zn)₉₂, La₃(Mg,Zn)₁₁ and La_4.27Mg_2.89Zn₃₀). The enthalpies of mixing in the ternary solid solutions are calculated at 298 K on the basis of tin solution calorimetry experiments.     

Phase Equilibria of the Al-Co-Zn System at 450 °C

The 450 °C isothermal section of the Al-Co-Zn ternary system was determined experimentally by means of scanning electronic microscopy coupled with wave dispersive x-ray spectroscopy, and x-ray powder diffraction. Nine three-phase regions have been confirmed experimentally. The liquid phase is in equilibrium with all Al-Co compounds except Al₃Co. The maximum solubility of Zn in AlCo, Al₅Co₂, Al₉Co₂ and Al₁₃Co₄ is 8.76, 18.14, 1.24, 8.97 at.%, respectively. The Al solubility in the Co-Zn compounds (γ₂, γ₁, γ, β₁) is very small, no more than 0.14, 0.28, 0.32, and 0.62 at.%, respectively. No true ternary compound was found in the present study.