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Materials Data on ZrTi(CrFe)2 by Materials Project

ZrTi(CrFe)2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Zr sites. In the first Zr site, Zr is bonded in a 6-coordinate geometry to three equivalent Zr, one Ti, five Cr, and seven Fe atoms. There are two shorter (3.04 Å) and one longer (3.06 Å) Zr–Zr bond lengths. The Zr–Ti bond length is 2.94 Å. There are a spread of Zr–Cr bond distances ranging from 2.90–2.97 Å. There are a spread of Zr–Fe bond distances ranging from 2.86–2.96 Å. In the second Zr site, Zr is bonded in a 12-coordinate geometry to three equivalent Zr, one Ti, seven Cr, and five Fe atoms. The Zr–Ti bond length is 2.99 Å. There are a spread of Zr–Cr bond distances ranging from 2.88–2.92 Å. There are a spread of Zr–Fe bond distances ranging from 2.89–2.93 Å. There are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a 12-coordinate geometry to one Zr, three equivalent Ti, seven Cr, and five Fe atoms. There are two shorter (2.99 Å) and one longer (3.00 Å) Ti–Ti bond lengths. There are a spread of Ti–Cr bond distances ranging from 2.86–2.91 Å. There are a spread of Ti–Fe bond distances ranging from 2.75–2.86 Å. In the second Ti site, Ti is bonded in a 1-coordinate geometry to one Zr, three equivalent Ti, five Cr, and seven Fe atoms. There are a spread of Ti–Cr bond distances ranging from 2.73–2.90 Å. There are a spread of Ti–Fe bond distances ranging from 2.76–2.88 Å. There are three inequivalent Cr sites. In the first Cr site, Cr is bonded to six Ti, two equivalent Cr, and four Fe atoms to form distorted CrTi6Cr2Fe4 cuboctahedra that share corners with four equivalent CrZr3Ti3Cr4Fe2 cuboctahedra, corners with eight FeZr3Ti3Cr6 cuboctahedra, edges with six equivalent CrTi6Cr2Fe4 cuboctahedra, faces with eight CrZr6Cr2Fe4 cuboctahedra, and faces with twelve FeZr3Ti3Cr6 cuboctahedra. Both Cr–Cr bond lengths are 2.40 Å. There are a spread of Cr–Fe bond distances ranging from 2.40–2.42 Å. In the second Cr site, Cr is bonded to six Zr, two equivalent Cr, and four Fe atoms to form CrZr6Cr2Fe4 cuboctahedra that share corners with four equivalent CrZr3Ti3Cr4Fe2 cuboctahedra, corners with eight FeZr3Ti3Cr6 cuboctahedra, edges with six equivalent CrZr6Cr2Fe4 cuboctahedra, faces with eight CrTi6Cr2Fe4 cuboctahedra, and faces with twelve FeZr3Ti3Cr6 cuboctahedra. Both Cr–Cr bond lengths are 2.51 Å. There are three shorter (2.51 Å) and one longer (2.53 Å) Cr–Fe bond lengths. In the third Cr site, Cr is bonded to three Zr, three Ti, four Cr, and two equivalent Fe atoms to form distorted CrZr3Ti3Cr4Fe2 cuboctahedra that share corners with eight CrTi6Cr2Fe4 cuboctahedra, corners with ten FeZr3Ti3Cr2Fe4 cuboctahedra, edges with two equivalent CrZr3Ti3Cr4Fe2 cuboctahedra, edges with four equivalent FeZr3Ti3Cr2Fe4 cuboctahedra, faces with eight FeZr3Ti3Cr6 cuboctahedra, and faces with ten CrTi6Cr2Fe4 cuboctahedra. There are one shorter (2.40 Å) and one longer (2.51 Å) Cr–Cr bond lengths. There are one shorter (2.41 Å) and one longer (2.55 Å) Cr–Fe bond lengths. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to three Zr, three Ti, and six Cr atoms to form FeZr3Ti3Cr6 cuboctahedra that share corners with four CrTi6Cr2Fe4 cuboctahedra, corners with fourteen FeZr3Ti3Cr6 cuboctahedra, edges with six FeZr3Ti3Cr6 cuboctahedra, faces with four equivalent FeZr3Ti3Cr2Fe4 cuboctahedra, and faces with fourteen CrTi6Cr2Fe4 cuboctahedra. In the second Fe site, Fe is bonded to three Zr, three Ti, two Cr, and four Fe atoms to form distorted FeZr3Ti3Cr2Fe4 cuboctahedra that share corners with eight FeZr3Ti3Cr6 cuboctahedra, corners with ten CrTi6Cr2Fe4 cuboctahedra, edges with two equivalent FeZr3Ti3Cr2Fe4 cuboctahedra, edges with four equivalent CrZr3Ti3Cr4Fe2 cuboctahedra, faces with eight CrTi6Cr2Fe4 cuboctahedra, and faces with ten FeZr3Ti3Cr6 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.42–2.52 Å. In the third Fe site, Fe is bonded to three Zr, three Ti, two Cr, and four equivalent Fe atoms to form distorted FeZr3Ti3Cr2Fe4 cuboctahedra that share corners with six FeZr3Ti3Cr6 cuboctahedra, corners with twelve CrTi6Cr2Fe4 cuboctahedra, edges with six FeZr3Ti3Cr6 cuboctahedra, faces with eight equivalent FeZr3Ti3Cr2Fe4 cuboctahedra, and faces with ten CrTi6Cr2Fe4 cuboctahedra.

36 MATERIALS SCIENCE↗

Materials Data on CrFe by Materials Project

FeCr crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Cr is bonded in a 12-coordinate geometry to four equivalent Cr and eight equivalent Fe atoms. All Cr–Cr bond lengths are 2.43 Å. There are four shorter (2.49 Å) and four longer (2.79 Å) Cr–Fe bond lengths. Fe is bonded in a 12-coordinate geometry to eight equivalent Cr and four equivalent Fe atoms. All Fe–Fe bond lengths are 2.43 Å.

36 MATERIALS SCIENCE↗

Materials Data on CrFe(BiO3)2 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗

Microstructural evolution in a precipitate-hardened (Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 ) 94 Ti 2 Al 4 multi-principal element alloy during high-pressure torsion

Multi-principal element alloys demonstrate high strength, thermal stability, and irradiation resistance, making them excellent candidate materials for applications in nuclear reactors and other harsh environments. Some studies have examined the use of high-pressure torsion to strengthen MPEAs through grain size reduction and strain hardening. However, no studies have investigated the effect of HPT on secondary phases (precipitates) within an MPEA. Two alloys, (Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 ) 94 Ti 2 Al 4 containing Ni(Ti, Al) B2 phase, and CrFe σ phase, and single-phase Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 , were fabricated by casting and heat treatment. Both alloys were then processed with HPT to study microstructural evolution. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the alloys before and after HPT processing. HPT processing produced a nanocrystalline structure in both alloys, but (Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 ) 94 Ti 2 Al 4 exhibited a significantly smaller grain size and higher dislocation density than Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 , with corresponding higher hardness. Before HPT, the (Fe 0.3 Ni 0.3 Mn 0.3 Cr 0.1 ) 94 Ti 2 Al 4 alloy consisted of large grain (~ 400 μm) and precipitates, including B2 of ~ 38 μm average size, B2 of ~ 0.7 μm average size, and small amounts of σ of ~ 1.5 μm average size. After HPT, the larger B2 precipitates were decreased in size and volume fraction, while the smaller B2 precipitates were completely dissolved; the σ precipitates appeared unaffected by HPT, likely due to their much higher hardness. Finally, observation of the B2 precipitate distribution along radial distance indicates that the strain caused the precipitates to fracture at intermediate strain (γ = 125) and dissolve at high strain (γ = 280).

36 MATERIALS SCIENCE↗