- Email: [email protected]
[O50] Phase equilibria and thermodynamic evaluation of the Co-Ta binary system
360
Y. DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415
This research was supported by the Czech Science Foundation (Project No. GA14-15576S), by the Project CEITEC–Central European Institute of Technology (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund, and by the Institute of Physics of Materials of the Academy of Sciences of the Czech Republic (Institutional Project No. RVO: 68081723).
[18] [19] [20] [21]
G. Kaptay, Acta Mater. 60 (2012) 6804. J. Brillo, R. Schmid-Fetzer, J. Mater. Sci 49 (2014) 3674. Z. Weltsch, A. Lovas, J. Takács, et al., Appl. Surf. Sci 268 (2013) 52. G. Kaptay, J. Mater. Sci. 47 (2012) 8320.
http://dx.doi.org/10.1016/j.calphad.2015.01.056
References [1] J. Vřešťál, J. Štrof, J. Pavlů, Calphad 37 (2012) 37–48. [2] C. Servant, J. Phase Equilib. Diff 26 (2005) 39–49.
http://dx.doi.org/10.1016/j.calphad.2015.01.055
[O49] Calphad-compatible models for interfacial energies George Kaptay, Csaba Mekler, Adam Vegh
The Butler equation [1] is claimed here to be the root equation for the Gibbs adsorption equation [2], for the Langmuir adsorption equation [3] and for the empirical Szyszkowszki equation [4], describing the concentration dependence of surface tension (see also the work of Frumkin, connecting the latter three papers [5]). Thus, the Butler equation is one of the basic thermodynamic equations, to be used in Calphad. The Butler equation has been proven useful and reasonably accurate in modelling surface tension of many binary and multi-component solutions [6-13]. The same method was also successfully extended to predict the surface phase transition [14-16] (¼ complexion transition [17]) in potentially immiscible liquid solutions, the interfacial energy in liquid/liquid and coherent solid/solid alloys [18-19], the contact angle in non-reactive liquid alloy / solid systems [20] and the surface tension of nanophases [21].
Acknowledgements The results were achieved within the TÁMOP-4.2.1.B-10/2/ KONV-2010-0001 and the TÁMOP-4.2.2.A-11/1/KONV-2012-0019 projects (New Széchenyi Plan, supported by the European Union, and co-financed by the European Social Fund).
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17]
J.A.V. Butler, Proc. Roy. Soc. A135 (1932) 348. J.W. Gibbs, Trans. Conn. Acad. Arts Sci. 3 (108-248) (1875-1878) 343. I Langmuir, J. Am. Chem. Soc. 40 (1918) 1361. von B. Szyszkowski, Z. Phys. Chem. 64 (1908) 385. A. Frumkin, Z. Phys. Chem 116 (1925) 466–484. T.P. Hoar, D.A. Melford, Trans. Farad. Soc 53 (1957) 315. T. Tanaka, K. Hack, T. Iida, et al., Z. Metallkunde 87 (1996) 380. W. Gasior, Z. Moser, J. Pstrus, J. Phase Equilibria 22 (2001) 20. M. Kucharski, P. Fima, Arch. Metall. Mater. 49 (2004) 565. J. Brillo, Y. Plevachuk, I. Egry, J. Mater. Sci. 45 (2010) 5150. G. Garzel, J. Janczak-Rusch, L. Zabdyr, Calphad 36 (2012) 52. J. Sopousek, J. Vrestal, J. Pinkas, et al., J. Calphad 45 (2014) 33. J. Lee, K.J. Sim, Calphad 44 (2014) 129. G. Kaptay, Calphad 29 (56) (2005) 262. C. Mekler, G. Kaptay, Mater. Sci. Eng. A 495 (2008) 65. T. Sándor, C. Mekler, J. Dobránszky, et al., Metall. Mater. Trans.A 44 (2013) 351. P.R. Cantwell, M. Tang, S.J. Dillon, et al., Acta Mater 62 (2014) 1.
[O50] Phase equilibria and thermodynamic evaluation of the Co-Ta binary system Kazuya Shinagawa, Hibiki Chinen, Toshihiro Omori, Katsunari Oikawa, Ikuo Ohnuma, Kiyohito Ishida, Ryosuke Kainuma
Recently, Sato et al. found a microstructure similar to that of Nibase superalloys, that is, cuboidal γ’Co3(Al, W) (L12) particles coherently and densely precipitated in Co-rich γ(A1) matrix in the Co-Al-W ternary system [1]. Additional Ta tends to be distributed in the γ’ phase, which results in a considerable increase of the γ’ solvus temperature compared with other elements [2,3]. In order to control the microstructure as well as to optimize heattreatment conditions, precise information on phase equilibria in the Co base systems and the effect of alloying elements should be understood. However, the phase diagram of the Co-Ta binary system, which was determined by thermal analysis, X-ray diffraction and metallography many years ago, still has room for improvement. In this study, experimental investigation and thermodynamic evaluation of the Co-Ta binary phase diagram was carried out. Equilibrium compositions obtained in two-phase alloys and diffusion couples were measured by electron probe micro-analyzer (EPMA). A very narrow λ3(C36) þ λ2(C15) two-phase region is confirmed to be present around 26.5at.% Ta at temperatures between 9501C and 14481C. Equilibrium relationships above 15001C among the liquid, Laves (λ1(C14), λ2 and λ3, whose stoichiometry is described by Co2Ta), μ(D8b) and CoTa2(C16) phases were investigated by microstructural examination in ascast Co-(24-60at.%)Ta alloys. The solvus temperature of the γ’ Co3Ta (L12) phase precipitated in the 5.8at.%Ta γ(Co) and the peritectoid temperature of the Co7Ta2 phase in an 8.5at.%Ta alloy were determined to be 10131C and 10331C, respectively, by differential scanning calorimeter (DSC). Fine precipitates of the γ’ phase precipitated in the (A1) matrix were observed by transmission electron microscope (TEM). Analyzing the present experimental results synthetically, the γ’ Co3Ta phase was identified to be a metastable phase, of which the γ’/γ order-disorder transition temperature of the stoichiometric Co3Ta alloy was estimated to be 20001C. Thermodynamic assessment of the Co-Ta binary system was carried out based on the present results as well as on experimental data in the literature. Calculated results of not only stable but also metastable equilibria were found to be in good agreement with the revised phase diagram. The evaluated stability of the metastable γ’ Co3Ta coincides with the enthalpy of formation (ΔH(γ’Co3Ta) ¼ -23.44 kJ/mol) calculated by the ab initio method [3].
References [1] J Sato, T Ohmori, K Oikawa, I Ohnuma, R Kainuma, K Ishida, Science 312 (2006) 90.
Y DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415
[2] M Ooshima, K Tanaka, N.L Okamoto, K Ishida, H Inui, J Alloys and Compounds 508 (2010) 71. [3] T Omori, K Oikawa, J Sato, I Ohnuma, U.R. Kattner, R Kainuma, K Ishida, Intermetallics 32 (2013) 274.
http://dx.doi.org/10.1016/j.calphad.2015.01.057
[O53] Prediction of the phase diagram of Sn-Ag nanoparticles Joonho Lee, Kijoo Sim Chemical potential of nanoparticles is different from that of bulk material due to the surface effect. Tanaka and Hara suggested that the phase diagram of metallic nanoparticles can be predicted by using the bulk thermodynamic database coupled with the bulk thermophysical properties of pure substances [1, 2]. Later, Park and Lee suggested that the phase diagram of metallic nanoparticles can be calculated according to the CALPHAD method by introducing the size effect [3], and recently we have reported more generalize form of the CALPHAD-type description of the thermodynamic parameters, as functions of temperature, composition and particle size under isothermal condition [4]. This method has been applied to oxides system as well [5]. In this study, thermodynamic parameters for the Ag-Sn nanoparticle system (pure substances of Ag and Sn, intermetallic compound of Ag3Sn, solid solutions of fcc, hcp, and bct, and liquid) were optimized as a function of temperature and particle’s radius. Phase stability of Ag3Sn is sensitive to the selection of the surface tension value for Ag3Sn. However, the eutectic temperature and composition do not depend on the phase stability of Ag3Sn so much. As the particle size decreases, the eutectic temperature decreases and the eutectic composition moves to the Sn-rich corner. The present calculation results showed reasonable agreement with the reported experimental data. The present results were reported in our recent publication [6]. This research was supported by the Space Core Technology Development Program (2012M1A3A3A02033446) and the Converging Research Center Program (2013K000302) through the Ministry of Science, ICT & Future Planning. References [1] [2] [3] [4] [5] [6]
T. Tanaka, S. Hara, Z. Metallkd 92 (2001) 467. T. Tanaka, S. Hara, Z. Metallkd 92 (2001) 1236. J. Park, J. Lee, CALPHAD 32 (2008) 135. J. Lee, K.J. Sim, CALPHAD 44 (2014) 129. S.S. Kim, J. Alloy Compd 588 (2014) 697. K. Sim, J. Lee, J. Alloy Compd 590 (2014) 140.
http://dx.doi.org/10.1016/j.calphad.2015.01.058
[O54] Studies on hydrogen storage materials from the Li-B and Ca-Li systems Władysław Gąsior, Marek Polański, Janusz Pstruś, Adam Dębski Keywords: BLi phase; Hydrogen absorption/ desorption; Hydrogen storage
Investigations on the hydrogen storage materials which belong to B-Li and Ca-Li systems have been continued in ZAMAT project POIG.01.01.02-00-015/09-00. A plan of project has been focused
361
the calorimetric measurements of formation enthalpies of intermediate phases and the hydrogenation of alloys and phases. A part of results were presented in papers and conferences [1-3] and concerned to the enthalpy of formation and hydrogenation of Li-B and studies of LiBH4 compound. The studies of the LiBH4 dehydrogenations were continued under different pressures and temperatures. In the next stage the investigations were directed at the nitrification of Ca-Li solid alloys, Li and Ca and theirs hydrogenation. The samples were prepared in the high purity argon protective atmosphere. The nitrides samples were hydrogenated at different temperatures and under different pressure. The studies showed that the nitrification process goes were easy and fast at elevated temperatures what was to predict similar as the hydrogenation. The hydrogenation was conducted using powder and solid samples. The desorption preliminary studies of hydrogen from hydrogenated nitrides was found to be easy et elevated temperatures however it was impossible to repeat absorption/ desorption process many times. The experiment will be conducted using powder samples. The experiments of the H2 absorption at graphen flakes are also planned in the next stage of ZAMAT investigation program.
References [1] W. Gąsior, A. Dębski, R. Major, Ł. Major, A. Góral, Intermetallics 24 (2012) 120. [2] W. Gąsior, A. Dębski, A. Góral, R. Major, Archives of Metallurgy and Materials 59 (2014) 297. [3] W. Gąsior, M. Polański, CALPHAD XLI, 3-8.06.2012 Berkeley, USA.
http://dx.doi.org/10.1016/j.calphad.2015.01.059
[O55] Electronic Structures and Formation Mechanism of Nd-O in Nd-Fe-B Magnets Arkapol Saengdeejing, Ying Chen, Ken Suzuki, Hideo Miura, Masashi Matsuura, Satoshi Sugimoto
A disordered NdOx-fcc phase formed at the interface between pure Nd and Nd-Fe-B permanent magnet materials is observed [1] and believed to take an important role in coercivity enhancement. In order to understand the electronic structures and formation mechanism of this particular oxide phases, ground state investigation for the whole oxygen composition range is needed. First-principles calculations that based on density functional theory coupled (LSDA þU) with cluster expansion method (CEM) are performed to explore the ground state structures of disordered NdOx-fcc. In this work, cluster expansion method is performed on series structures by introducing oxygen vacancies into different base structures such as NdO (ZnS structure), NdO2 (CaF2 structure), Nd2O3-hP5, and Nd2O3-cl80 system. The results shows that the stability of fcc-based series of structures formed by introducing oxygen vacancies into NdO are stable in a wide oxygen concentration range, whereas in a series hcp-based structures developed from Nd2O3-hP5, the most stable structure in Nd-O system, no stable structures are observed, which agrees well with experimental study [2]. Combining with the formation energies, lattice distortion and relevant electronic structure data of single oxygen vacancy calculated for various structures, we can reveals some insightful information of the formation of fccbased phase.
Y. DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415
This research was supported by the Czech Science Foundation (Project No. GA14-15576S), by the Project CEITEC–Central European Institute of Technology (CZ.1.05/1.1.00/02.0068) from the European Regional Development Fund, and by the Institute of Physics of Materials of the Academy of Sciences of the Czech Republic (Institutional Project No. RVO: 68081723).
[18] [19] [20] [21]
G. Kaptay, Acta Mater. 60 (2012) 6804. J. Brillo, R. Schmid-Fetzer, J. Mater. Sci 49 (2014) 3674. Z. Weltsch, A. Lovas, J. Takács, et al., Appl. Surf. Sci 268 (2013) 52. G. Kaptay, J. Mater. Sci. 47 (2012) 8320.
http://dx.doi.org/10.1016/j.calphad.2015.01.056
References [1] J. Vřešťál, J. Štrof, J. Pavlů, Calphad 37 (2012) 37–48. [2] C. Servant, J. Phase Equilib. Diff 26 (2005) 39–49.
http://dx.doi.org/10.1016/j.calphad.2015.01.055
[O49] Calphad-compatible models for interfacial energies George Kaptay, Csaba Mekler, Adam Vegh
The Butler equation [1] is claimed here to be the root equation for the Gibbs adsorption equation [2], for the Langmuir adsorption equation [3] and for the empirical Szyszkowszki equation [4], describing the concentration dependence of surface tension (see also the work of Frumkin, connecting the latter three papers [5]). Thus, the Butler equation is one of the basic thermodynamic equations, to be used in Calphad. The Butler equation has been proven useful and reasonably accurate in modelling surface tension of many binary and multi-component solutions [6-13]. The same method was also successfully extended to predict the surface phase transition [14-16] (¼ complexion transition [17]) in potentially immiscible liquid solutions, the interfacial energy in liquid/liquid and coherent solid/solid alloys [18-19], the contact angle in non-reactive liquid alloy / solid systems [20] and the surface tension of nanophases [21].
Acknowledgements The results were achieved within the TÁMOP-4.2.1.B-10/2/ KONV-2010-0001 and the TÁMOP-4.2.2.A-11/1/KONV-2012-0019 projects (New Széchenyi Plan, supported by the European Union, and co-financed by the European Social Fund).
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17]
J.A.V. Butler, Proc. Roy. Soc. A135 (1932) 348. J.W. Gibbs, Trans. Conn. Acad. Arts Sci. 3 (108-248) (1875-1878) 343. I Langmuir, J. Am. Chem. Soc. 40 (1918) 1361. von B. Szyszkowski, Z. Phys. Chem. 64 (1908) 385. A. Frumkin, Z. Phys. Chem 116 (1925) 466–484. T.P. Hoar, D.A. Melford, Trans. Farad. Soc 53 (1957) 315. T. Tanaka, K. Hack, T. Iida, et al., Z. Metallkunde 87 (1996) 380. W. Gasior, Z. Moser, J. Pstrus, J. Phase Equilibria 22 (2001) 20. M. Kucharski, P. Fima, Arch. Metall. Mater. 49 (2004) 565. J. Brillo, Y. Plevachuk, I. Egry, J. Mater. Sci. 45 (2010) 5150. G. Garzel, J. Janczak-Rusch, L. Zabdyr, Calphad 36 (2012) 52. J. Sopousek, J. Vrestal, J. Pinkas, et al., J. Calphad 45 (2014) 33. J. Lee, K.J. Sim, Calphad 44 (2014) 129. G. Kaptay, Calphad 29 (56) (2005) 262. C. Mekler, G. Kaptay, Mater. Sci. Eng. A 495 (2008) 65. T. Sándor, C. Mekler, J. Dobránszky, et al., Metall. Mater. Trans.A 44 (2013) 351. P.R. Cantwell, M. Tang, S.J. Dillon, et al., Acta Mater 62 (2014) 1.
[O50] Phase equilibria and thermodynamic evaluation of the Co-Ta binary system Kazuya Shinagawa, Hibiki Chinen, Toshihiro Omori, Katsunari Oikawa, Ikuo Ohnuma, Kiyohito Ishida, Ryosuke Kainuma
Recently, Sato et al. found a microstructure similar to that of Nibase superalloys, that is, cuboidal γ’Co3(Al, W) (L12) particles coherently and densely precipitated in Co-rich γ(A1) matrix in the Co-Al-W ternary system [1]. Additional Ta tends to be distributed in the γ’ phase, which results in a considerable increase of the γ’ solvus temperature compared with other elements [2,3]. In order to control the microstructure as well as to optimize heattreatment conditions, precise information on phase equilibria in the Co base systems and the effect of alloying elements should be understood. However, the phase diagram of the Co-Ta binary system, which was determined by thermal analysis, X-ray diffraction and metallography many years ago, still has room for improvement. In this study, experimental investigation and thermodynamic evaluation of the Co-Ta binary phase diagram was carried out. Equilibrium compositions obtained in two-phase alloys and diffusion couples were measured by electron probe micro-analyzer (EPMA). A very narrow λ3(C36) þ λ2(C15) two-phase region is confirmed to be present around 26.5at.% Ta at temperatures between 9501C and 14481C. Equilibrium relationships above 15001C among the liquid, Laves (λ1(C14), λ2 and λ3, whose stoichiometry is described by Co2Ta), μ(D8b) and CoTa2(C16) phases were investigated by microstructural examination in ascast Co-(24-60at.%)Ta alloys. The solvus temperature of the γ’ Co3Ta (L12) phase precipitated in the 5.8at.%Ta γ(Co) and the peritectoid temperature of the Co7Ta2 phase in an 8.5at.%Ta alloy were determined to be 10131C and 10331C, respectively, by differential scanning calorimeter (DSC). Fine precipitates of the γ’ phase precipitated in the (A1) matrix were observed by transmission electron microscope (TEM). Analyzing the present experimental results synthetically, the γ’ Co3Ta phase was identified to be a metastable phase, of which the γ’/γ order-disorder transition temperature of the stoichiometric Co3Ta alloy was estimated to be 20001C. Thermodynamic assessment of the Co-Ta binary system was carried out based on the present results as well as on experimental data in the literature. Calculated results of not only stable but also metastable equilibria were found to be in good agreement with the revised phase diagram. The evaluated stability of the metastable γ’ Co3Ta coincides with the enthalpy of formation (ΔH(γ’Co3Ta) ¼ -23.44 kJ/mol) calculated by the ab initio method [3].
References [1] J Sato, T Ohmori, K Oikawa, I Ohnuma, R Kainuma, K Ishida, Science 312 (2006) 90.
Y DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415
[2] M Ooshima, K Tanaka, N.L Okamoto, K Ishida, H Inui, J Alloys and Compounds 508 (2010) 71. [3] T Omori, K Oikawa, J Sato, I Ohnuma, U.R. Kattner, R Kainuma, K Ishida, Intermetallics 32 (2013) 274.
http://dx.doi.org/10.1016/j.calphad.2015.01.057
[O53] Prediction of the phase diagram of Sn-Ag nanoparticles Joonho Lee, Kijoo Sim Chemical potential of nanoparticles is different from that of bulk material due to the surface effect. Tanaka and Hara suggested that the phase diagram of metallic nanoparticles can be predicted by using the bulk thermodynamic database coupled with the bulk thermophysical properties of pure substances [1, 2]. Later, Park and Lee suggested that the phase diagram of metallic nanoparticles can be calculated according to the CALPHAD method by introducing the size effect [3], and recently we have reported more generalize form of the CALPHAD-type description of the thermodynamic parameters, as functions of temperature, composition and particle size under isothermal condition [4]. This method has been applied to oxides system as well [5]. In this study, thermodynamic parameters for the Ag-Sn nanoparticle system (pure substances of Ag and Sn, intermetallic compound of Ag3Sn, solid solutions of fcc, hcp, and bct, and liquid) were optimized as a function of temperature and particle’s radius. Phase stability of Ag3Sn is sensitive to the selection of the surface tension value for Ag3Sn. However, the eutectic temperature and composition do not depend on the phase stability of Ag3Sn so much. As the particle size decreases, the eutectic temperature decreases and the eutectic composition moves to the Sn-rich corner. The present calculation results showed reasonable agreement with the reported experimental data. The present results were reported in our recent publication [6]. This research was supported by the Space Core Technology Development Program (2012M1A3A3A02033446) and the Converging Research Center Program (2013K000302) through the Ministry of Science, ICT & Future Planning. References [1] [2] [3] [4] [5] [6]
T. Tanaka, S. Hara, Z. Metallkd 92 (2001) 467. T. Tanaka, S. Hara, Z. Metallkd 92 (2001) 1236. J. Park, J. Lee, CALPHAD 32 (2008) 135. J. Lee, K.J. Sim, CALPHAD 44 (2014) 129. S.S. Kim, J. Alloy Compd 588 (2014) 697. K. Sim, J. Lee, J. Alloy Compd 590 (2014) 140.
http://dx.doi.org/10.1016/j.calphad.2015.01.058
[O54] Studies on hydrogen storage materials from the Li-B and Ca-Li systems Władysław Gąsior, Marek Polański, Janusz Pstruś, Adam Dębski Keywords: BLi phase; Hydrogen absorption/ desorption; Hydrogen storage
Investigations on the hydrogen storage materials which belong to B-Li and Ca-Li systems have been continued in ZAMAT project POIG.01.01.02-00-015/09-00. A plan of project has been focused
361
the calorimetric measurements of formation enthalpies of intermediate phases and the hydrogenation of alloys and phases. A part of results were presented in papers and conferences [1-3] and concerned to the enthalpy of formation and hydrogenation of Li-B and studies of LiBH4 compound. The studies of the LiBH4 dehydrogenations were continued under different pressures and temperatures. In the next stage the investigations were directed at the nitrification of Ca-Li solid alloys, Li and Ca and theirs hydrogenation. The samples were prepared in the high purity argon protective atmosphere. The nitrides samples were hydrogenated at different temperatures and under different pressure. The studies showed that the nitrification process goes were easy and fast at elevated temperatures what was to predict similar as the hydrogenation. The hydrogenation was conducted using powder and solid samples. The desorption preliminary studies of hydrogen from hydrogenated nitrides was found to be easy et elevated temperatures however it was impossible to repeat absorption/ desorption process many times. The experiment will be conducted using powder samples. The experiments of the H2 absorption at graphen flakes are also planned in the next stage of ZAMAT investigation program.
References [1] W. Gąsior, A. Dębski, R. Major, Ł. Major, A. Góral, Intermetallics 24 (2012) 120. [2] W. Gąsior, A. Dębski, A. Góral, R. Major, Archives of Metallurgy and Materials 59 (2014) 297. [3] W. Gąsior, M. Polański, CALPHAD XLI, 3-8.06.2012 Berkeley, USA.
http://dx.doi.org/10.1016/j.calphad.2015.01.059
[O55] Electronic Structures and Formation Mechanism of Nd-O in Nd-Fe-B Magnets Arkapol Saengdeejing, Ying Chen, Ken Suzuki, Hideo Miura, Masashi Matsuura, Satoshi Sugimoto
A disordered NdOx-fcc phase formed at the interface between pure Nd and Nd-Fe-B permanent magnet materials is observed [1] and believed to take an important role in coercivity enhancement. In order to understand the electronic structures and formation mechanism of this particular oxide phases, ground state investigation for the whole oxygen composition range is needed. First-principles calculations that based on density functional theory coupled (LSDA þU) with cluster expansion method (CEM) are performed to explore the ground state structures of disordered NdOx-fcc. In this work, cluster expansion method is performed on series structures by introducing oxygen vacancies into different base structures such as NdO (ZnS structure), NdO2 (CaF2 structure), Nd2O3-hP5, and Nd2O3-cl80 system. The results shows that the stability of fcc-based series of structures formed by introducing oxygen vacancies into NdO are stable in a wide oxygen concentration range, whereas in a series hcp-based structures developed from Nd2O3-hP5, the most stable structure in Nd-O system, no stable structures are observed, which agrees well with experimental study [2]. Combining with the formation energies, lattice distortion and relevant electronic structure data of single oxygen vacancy calculated for various structures, we can reveals some insightful information of the formation of fccbased phase.