Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Mg-Re”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Experimental characterization and atomistic simulation of grain boundary segregation in Mg-Y alloys

As a rare earth solute element in Mg alloys, Y has the beneficial effects of increasing both the strength and the ductility as well as weakening the crystallographic texture. To achieve a more fundamental understanding on how Y addition affects the microstructural evolution and mechanical properties, the Y segregation behavior at grain boundaries was investigated in Mg-1wt.%Y and Mg-7wt.%Y alloys at different conditions. The segregation intensity and its dependence on the grain boundary misorientation angle were experimentally characterized and computationally predicted. Strong segregation at grain boundaries was observed in both low and high Y-containing alloys. Y segregation was found to remain in alloy Mg-7Y after high-temperature annealing heat treatment at 540 °C. No direct correlation between the Y segregation intensity and the grain boundary misorientation angle could be established based on either the experimental characterization or the atomistic simulation with a spectral model. We thus conclude that grain boundary segregation of Y is independent of grain boundary misorientation angle.

Grain boundary↗
DOE OSTI2022

Partitioning of Ca to metastable precipitates in a Mg-rare earth alloy

The potential effect of the element Ca on the precipitation behavior was investigated in an Mg-rare earth alloy. A combination of metastable β''' and β' precipitates was observed for the peak aging condition at 200°C. Ca addition was found to have no significant effect on the precipitating phases and evolution sequence. Composition analysis showed that the Ca partitioned to both β''' and β' precipitate phases. First-principles calculations indicated that Ca partitions to the rare-earth sublattice in the precipitate phase. This finding suggests the potential of Ca to partially replace costly rare-earth elements in precipitation-hardened Mg-rare earth alloys.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Re by Materials Project

Mg3Re is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Mg is bonded to eight equivalent Mg and four equivalent Re atoms to form distorted MgMg8Re4 cuboctahedra that share corners with twelve equivalent MgMg8Re4 cuboctahedra, edges with eight equivalent ReMg12 cuboctahedra, edges with sixteen equivalent MgMg8Re4 cuboctahedra, faces with four equivalent ReMg12 cuboctahedra, and faces with fourteen equivalent MgMg8Re4 cuboctahedra. All Mg–Mg bond lengths are 2.94 Å. All Mg–Re bond lengths are 2.94 Å. Re is bonded to twelve equivalent Mg atoms to form ReMg12 cuboctahedra that share corners with twelve equivalent ReMg12 cuboctahedra, edges with twenty-four equivalent MgMg8Re4 cuboctahedra, faces with six equivalent ReMg12 cuboctahedra, and faces with twelve equivalent MgMg8Re4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgRe3 by Materials Project

MgRe3 is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg is bonded in a distorted body-centered cubic geometry to fourteen Re atoms. There are eight shorter (2.70 Å) and six longer (3.11 Å) Mg–Re bond lengths. There are two inequivalent Re sites. In the first Re site, Re is bonded to four equivalent Mg and four equivalent Re atoms to form a mixture of distorted edge, face, and corner-sharing ReMg4Re4 tetrahedra. All Re–Re bond lengths are 2.70 Å. In the second Re site, Re is bonded in a 8-coordinate geometry to six equivalent Mg and eight equivalent Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Re by Materials Project

Mg3Re is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Mg is bonded to eight equivalent Mg and four equivalent Re atoms to form distorted MgMg8Re4 cuboctahedra that share corners with four equivalent ReMg12 cuboctahedra, corners with fourteen equivalent MgMg8Re4 cuboctahedra, edges with six equivalent ReMg12 cuboctahedra, edges with twelve equivalent MgMg8Re4 cuboctahedra, faces with four equivalent ReMg12 cuboctahedra, and faces with sixteen equivalent MgMg8Re4 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.81–3.10 Å. There are two shorter (2.90 Å) and two longer (2.96 Å) Mg–Re bond lengths. Re is bonded to twelve equivalent Mg atoms to form ReMg12 cuboctahedra that share corners with six equivalent ReMg12 cuboctahedra, corners with twelve equivalent MgMg8Re4 cuboctahedra, edges with eighteen equivalent MgMg8Re4 cuboctahedra, faces with eight equivalent ReMg12 cuboctahedra, and faces with twelve equivalent MgMg8Re4 cuboctahedra.

36 MATERIALS SCIENCE↗