Mechanical properties of refractory high-entropy alloys: Experiments and modeling

Synthesis and characterization of multicomponent (CrNbTaTiW)C films for increased hardness and corrosion resistance

“…For all films the cubic B1 structure has been used for indexing. The NBD patterns of NEC300 prove that columns in two different crystal orientations [1][2][3][4][5][6][7][8][9][10] and [0−11] coexist. By combining these two diffraction patterns, all reflections in the SAED pattern of NEC300 can be identified, as shown in the overlayed pattern.…”

“…By combining these two diffraction patterns, all reflections in the SAED pattern of NEC300 can be identified, as shown in the overlayed pattern. The overlap of the 111-reflections for the [1][2][3][4][5][6][7][8][9][10] and [0-11] zone axes indicates that the two different orientations share a common (111) lattice plane. Since there is space between the single columns, no atomically close twin boundaries between the single columns are expected.…”

“…Using this approach, most reflections in the SAED could be identified as depicted in the overlay. For NEC600, a dense grain structure with small domains is observed and therefore a high twin boundary density is expected in which the dominant [1][2][3][4][5][6][7][8][9][10] and [0-11] twin zone axes share a common (111) lattice plane. The SAED pattern of the TaWC300 film can be indexed with the zone axis as depicted in the simulated diffraction pattern and the according overlay.…”

“…The results show that incorporation of low amounts of carbon results in an increase in strength due to precipitation and grain boundary hardening. While bulk refractory high entropy alloys have been studied in detail by experimental [6][7][8][9][10][11] and computational [12][13][14] material science, there are only a few studies published on the addition of carbon to HEAs based on strong carbide formers such as the early transition metal in group 4 and 5 [5,15,16]. Braic et al have shown that (TiZrNbHfTa)C with a B1 structure with C in the octahedral sites can be synthesised by co-sputtering in a reactive atmosphere [15].…”

Short communication: ‘Low activation, refractory, high entropy alloys for nuclear applications’

“…HEAs based on refractory elements of the 4-5-6 alloy group (named from the groups and periods in the periodic table) show considerable potential for structural applications [14]. Alloys of the NbTaV -(Ti, W, Mo) system, that have a disordered BCC structure, have been proposed as high temperature materials that offer high strength, ductility and oxidation resistance [15,16]. The alloy TiVNbTa shows excellent compressive mechanical properties at room temperature (y = 1273 MPa) and at elevated temperatures (y drops to 688 MPa at 900 • C) [17].…”