Experimental investigations and thermodynamic modelling of the Cr–Nb–Sn–Zr system

Abstract

This work reports the Calphad modelling of the Cr-Nb-Sn-Zr quaternary system. In a previous paper, the thermodynamic modelling of the Cr-Nb-Sn system has been presented. Since no experimental data were available for the Cr-Sn-Zr ternary system, new experimental data are provided, within this study, on the isothermal section at 900 °C. A ternary C14 phase has been identified on the Sn-poor side of the phase diagram. In addition to these experimental data, Density Functional Theory (DFT) calculations are carried out in order to determine formation enthalpies of the stable and metastable phases. At last, the Special Quasirandom Structures (SQS) method is jointly used with DFT calculations in order to estimate the mixing enthalpies of the A2 and A3 binary solid solutions. Finally, these experimental and calculated data in addition to those from the literature, are used as input data for the Calphad modelling of the Cr-Zr, Nb-Zr and Sn-Zr binary systems and the Cr-Nb-Zr, Cr-Sn-Zr and Nb-Sn-Zr ternary systems. A complete database for the Cr-Nb-Sn-Zr quaternary system is provided.

Thermodynamic modelling of the Fe–Sn–Zr system based on new experiments and first-principles calculations

“…The experimental procedure was identical to that employed in our previous work [17]. The samples have been synthesized from pieces of the pure elements (Fe from Neyco (99.99%),…”

“…Fe14.39Sn43.47Zr39.13 (X'') compounds have been calculated using VASP code [65,66]. The procedure was similar to that used in our previous work [17] including the calculation of all the configurations obtained by distributing the atoms in the C15 and C36 structures. The same code ZenGen [67], potentials [68] SQS calculations [70] were also conducted in the same way as previously [17] with A1, A2…”

“…The Calphad description of the Sn-Zr system has been published separately in a paper dedicated to the Cr-Nb-Sn-Zr quaternary system [17]. We present here new Calphad assessments of the Fe-Sn and Fe-Zr binary systems and the description of the Fe-Sn-Zr ternary system.…”

Experimental study, first-principles calculation and thermodynamic modelling of the Cr–Fe–Nb–Sn–Zr quinary system for application as cladding materials in nuclear reactors.

“…This paper presents the Calphad modelling of the Cr-Fe-Nb-Sn-Zr quinary system. In previous papers, we have already presented the thermodynamic modelling of the Cr-Nb-Sn ternary system [7], the Cr-Nb-Sn-Zr quaternary system reassessing all the binary and ternary subsystems [8], the Fe-Nb binary system and Fe-Nb-Zr ternary system [9] as well as the critical assessment of the Fe-Sn-Zr ternary system [10] based on new experimental and calculated data. Just note that a brief description of the Fe-Nb binary system and the Fe-Nb-Zr ternary system has been provided in our previous paper [9].…”

Phase transformations during cooling from the βZr phase temperature domain in several hydrogen-enriched zirconium alloys studied by in situ and ex situ neutron diffraction

“…The results are presented in Section 3 and then discussed in Section 4. They are compared to thermodynamic predictions at equilibrium obtained using the Thermo-Calc® software together with the Zircobase database [20] [21], taking into account all the chemical elements constituting the material (Zr, Nb, Sn, Fe, Cr, H and O). It must be mentioned that, so far, these thermodynamic predictions had not been experimentally validated on multicomponent (multi-alloyed) systems for the highest hydrogen contents studied here.…”