The constitution of the chromium-niobium-silicon system

A study of the microstructures and oxidation of Nb–Si–Cr–Al–Mo in situ composites alloyed with Ti, Hf and Sn

“…The compositions of the Laves phase formed in these alloys correspond well to the ternary r phase reported in Ref. [36], considering that the Si, Al and Sn substitute for Cr and Ti, Mo and Hf substitute for Nb. In the NbeSieCr ternary system, the r phase replaces the cubic C15eCr 2 Nb Laves phase at Si content of 2.5 at% and has a considerable solubility for Nb, Si and Cr [36].…”

“…As reported in Refs. [36,37], the Si-containing C14 Laves phase can be in direct equilibrium with the Nb ss and Nb 5 Si 3 phases in the NbeSie Cr ternary system, giving the Nb ss þ C14 þ Nb 5 Si 3 ternaryphase field. This ternary-phase equilibrium was observed in the as solidified microstructures of the alloys Nbe18Sie 5Ale5Cre5Mo (JG1), Nbe24Tie18Sie5Ale5Cre2Moe 5Hf (JG4) and Nbe24Tie18Sie5Ale5Cre5Moe2Hfe5Sn (JG6).…”

“…[36], considering that the Si, Al and Sn substitute for Cr and Ti, Mo and Hf substitute for Nb. In the NbeSieCr ternary system, the r phase replaces the cubic C15eCr 2 Nb Laves phase at Si content of 2.5 at% and has a considerable solubility for Nb, Si and Cr [36]. The EPMA data for JG1-AC, JG1-HT, JG4-AC, JG6-AC and JG6-HT alloys would thus suggest that the solubility range of Si in the Si-rich C14 Laves phase formed in alloys of the NbeTieSieCreAleMoeHfeSn system is approximately 6.6e10.5 at%.…”

Thermodynamic modelling of the Cr–Nb–Si system

“…A 1000 8C isothermal section of the Cr-Nb-Si system was reported by Goldschmidt and Brand in the early 1960s based on phase equilibrium data in 220 cast alloys which were annealed for 336 h for equilibration [17], as is shown in Fig. 1a.…”

Thermodynamic Description of Ternary Fe-X-P systems. Part 5: Fe-Nb-P

“…Figure 3 shows the calculated Fe-Nb phase diagram (reoptimized in the current study) as well as multiple experimental data. [14][15][16][17][18][19][20][21][22][23][24] On the whole, the current Fe-Nb optimization is a combination from those of Toffolon and Servant [6] and of Lee. [7] Although the thermodynamic data of the latter author was used as a reference due to its simplicity, it had to be modified in order to get a higher melting point for the k-phase (Fe 2 Nb) and to guarantee a peritectic formation of the l phase (Fe 7 Nb 6 ), as proposed by Toffolon and Servant [6] (see Fig.…”