[P31] Li-Be and B-Be systems – experimental study

[P31] Li-Be and B-Be systems – experimental study

382 Y. DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415 Quasichemical Model and the solid solutions we...

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382

Y. DU et al. / CALPHAD: Computer Coupling of Phase Diagrams and Thermochemistry 51 (2015) 344–415

Quasichemical Model and the solid solutions were treated within the framework of Compound Energy Formalism. http://dx.doi.org/10.1016/j.calphad.2015.01.119

[P31] Li-Be and B-Be systems – experimental study Przemysław Fima, Adam Dębski

The Li-Be and B-Be belong to a group of alloys that are not thermodynamically described. The phase diagrams of Li-Be [1] and B-Be [2] were published in the 1980s based on limited experimental data available at that time. Even by their authors the phase diagrams were described as tentative. Despite over 25 years that passed there are no new experimental data in the literature that would allow for thermodynamic assessment of the Li-Be and B-Be phase diagrams. Because of our experience in studies of thermodynamic properties of Li-based binary systems [3] we have attempted to study Li-Be and B-Be alloys. To facilitate it a number of experimental methods were employed including: induction melting, X-ray diffraction (XRD), drop calorimetry, differential thermal analysis (DTA) and electromotive force method (EMF).

Fig. 13. Isothermal section at 8001C.

Acknowledgments The financial support under the grant no. 2011/01/D/ST8/01630 of the Polish National Science Centre is gratefully acknowledged. Fig. 14. Phase diagram in Sn-rich corner at 6001C.

References [1] A.D. Pelton, Bull. Alloy Phase Diag 6 (1985) 30. [2] T.B. Massalski (Ed.), Binary alloy phase diagrams, 2nd ed.,ASM, 1990. [3] W. Gąsior, A. Dębski, et al., Intermetallics 24 (2012) 120.

http://dx.doi.org/10.1016/j.calphad.2015.01.120

[P32] Ternary compounds and phase equilibria in the Sn-Ni-V system Changjun Wu, Ya Liu, Xuping Su, Haoping Peng, Hao Tu, Jianhua Wang, Yifan Zhang

980 oC. VNi2Sn has wider composition range at this temperature. And there exist 9 three-phase regions at 980 oC. i.e., (1) V3SnþNi3Sn2 þLiq.; (2) Ni3Sn2 þV3SnþVNi2Sn; (3) VNi2SnþV3Snþσ’; (4) α-Vþ V3Snþσ’; (5) VNi2Snþ (Ni)2 þσ’; (6) VNi2Snþ(Ni)þ Ni3Sn2; (7) Ni3Sn2 þ(Ni)2 þ VNi3; (8) Ni3Sn2 þ(Ni)1 þVNi3; (9) Ni3Sn2 þNi3Snþ(Ni)1. No ternary compound was found at Sn-rich corner. There exist 3 three-phase equilibria of Ni3Sn4 þVSn2 þLiq., V3Snþ VSn2 þ Ni3Sn4 and V3Snþ Ni3Sn4 þ Ni3Sn2 in the Sn-rich corner at 300 oC and 600 oC (Fig. 14).

Acknowledgments The financial support from National Natural Science Foundation of China (Nos. 51201023 and 51171031) are greatly acknowledged.

The 800 oC and 980 oC isothermal sections and the Sn-rich corner at 300 oC and 600 oC of the Sn-Ni-V system were experimentally investigated using XRD, SEM-EDS/WDS and DTA, in the present work. All the three-phase equilibria were well determined and the solid solubilities of the third component in the binary compounds are obtained. Based on the experimental results, thermodynamic assessment of the system will carry out. Two ternary compounds, VNi2Sn and V2NiSn, exist in the system. VNi2Sn has wide composition range, while V2NiSn is near a stoichiometry compound. DTA test indicates that VNi2Sn (30V45Ni25Sn) has a melting congruent temperature around 1095.6 oC. As for the 800 oC section, as shown in Fig. 13, there exist 12 threephase regions. The composition range of the VNi2Sn spans 30.4 50.3 at.%V, 50.6 30.3 at.%Ni and 19.3 24.7 at.%Sn at 800 oC. V2NiSn can stable exist below 860 oC. The solubility of V in Ni3Sn2 reaches 30% at

http://dx.doi.org/10.1016/j.calphad.2015.01.121

[P33] Activity-Composition Relations and Thermodynamic Properties in Pt-V and Pt-Cr Alloys at 1500oC Yang Yang, Ragnhild E. Aune

The present work concerns the activity of vanadium and chromium in Pt-V and Pt-Cr alloy systems which may be used to