Ta-based 413 and 211 MAX phase solid solutions with Hf and Nb

First-principles calculation of phase equilibrium of V-Nb, V-Ta, and Nb-Ta alloys

In this paper, we report the calculated phase diagrams of V-Nb, V-Ta, and Nb-Ta alloys computed by combining the total energies of 40–50 configurations for each system (obtained using density functional theory) with the cluster expansion and Monte Carlo techniques. For V-Nb alloys, the phase diagram computed with conventional cluster expansion shows a miscibility gap with consolute temperature ...

ANION EXCHANGE BEHAVIOR OF Ti, Zr, Hf, Nb AND Ta AS HOMOLOGUES OF Rf AND Db IN MIXED HF-ACETONE SOLUTIONS

Phase Equilibria in Prototype Nb-Pd-Hf-Al Alloys

The phase equilibria in two prototype alloys with nominal compositions 60Nb-20Pd-10Hf-10Al and 40Nb-30Pd-15Hf-15Al (in at. pct) are investigated using scanning electron microscopy and X-ray diffraction. The alloys were heat treated at 1200 °C and 1500 °C for 200 hours each. The phase analysis revealed that the alloys were, for the most part, in the three-phase equilibrium between (Nb), Pd2HfAl,...

Influence of boron vacancies on phase stability, bonding and structure of MB₂ (M  =  Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W) with AlB₂ type structure.

Transition metal diborides in hexagonal AlB2 type structure typically form stable MB2 phases for group IV elements (M  =  Ti, Zr, Hf). For group V (M  =  V, Nb, Ta) and group VI (M  =  Cr, Mo, W) the stability is reduced and an alternative hexagonal rhombohedral MB2 structure becomes more stable. In this work we investigate the effect of vacancies on the B-site in hexagonal MB2 and its influenc...

the past hospitalization and its association with suicide attempts and ideation in patients with mdd and comparison with bmd (depressed type) group

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