Phase equilibria in the systems vanadium-chromium-carbon, niobium-chromium-carbon, and tantalum-chromium-carbon

An experimental and theoretical analysis of the phase equilibria in the Fe-Cr-V-C system

“…The maximum solubility of Cr in the MC carbide was reported to be around 38 at. pct at 1273 K [22] and around 25 at. pct at 1623 K, [20,21] whereas the Cr solubility in the M 2 C carbide at both temperatures was reported to be more than 30 at.…”

“…Both Cr and V are very strong carbide forming elements. Therefore, the ternary Cr-V-C system contains many different car- [20,21] and Fedorov et al [22] have reported two different experimental works on isothermal sections of the Cr-V-C system. The first work used alloys produced from 99.5 pct V, 99.3 pct Cr, and 99.95 pct C, and determined an isothermal section at 1623 K by an X-ray technique.…”

“…As can be seen previously, there is a very large difference in the Cr solubility in the MC carbide between the two different experimental works. If we chose to fit our ternary interaction parameter to the experimental information from Fedorov et al, [22] we would calculate more than 38 at. pct at 1623 K, and if instead the experimental information from Rassaerts et al [20,21] were used, we would calculate less than 25 at.…”

“…4-The calculated isothermal section of the Cr-V-C system at 1273 K with the present work thermodynamic parameters, in comparison with experimental data. [22] Fig. 5-The calculated isothermal section of the Cr-V-C system at 1623 K with the present work thermodynamic parameters, in comparison with experimental data.…”

Thermodynamic Modeling in Reduced Activation Steels

“…21) These values are close to those described by other authors for lower temperatures. 22,23) On the other hand, Ta was found in M 23 C 6 carbides after ageing the alloy F82H for up to 10 000 h 24) and, marginally, in the as-tempered state of the Eurofer97 11) and the 11Cr, RA Russian 25) steels. From the point of view of precipitation effects on mechanical properties of RA steels, coarsening of precipitates such as M 23 C 6 , M 6 C or Laves phases is known to diminish the material toughness at elevated temperatures.…”