Results for “Al-Mg-Zr” | Engineering Papers

DOE OSTI2020

Ultrafine-grained Al-Mg-Zr Alloy Processed by Shear-Assisted Extrusion with High Thermal Stability

Shear-assisted processing and extrusion (ShAPE) is used to consolidate Al-4.2Mg-1.6Zr-0.25Si-0.1Fe (wt.%) powders. The extruded alloy exhibits: (i) near-zero porosity; (ii) an attractive combination of tensile yield strength (~220 MPa), ultimate strength (330 MPa) and elongation (>20%); and (iii) excellent thermal stability at 400 ºC. The ultra-fine grain size in the gas-atomized powders – created and stabilized by primary L12-Al3Zr submicron precipitates - is maintained after consolidation and subsequent exposure at 400 ºC, contributing twice as much to strength as Mg in solid-solution. Electron microscopy reveals the microstructure of the L12-Al3Zr precipitates, and other precipitates (Mg2Si and Al3Fe) and dispersoids (oxides).

ShAPE, Friction Extrusion, aluminum powder, Shear ↗

NASA NTRS1990

Continuous recrystallization during thermomechanical processing of a superplastic Al-10Mg-0.1Zr alloy

Microstructural evolution via static continuous recrystallization during thermomechanical processing of an Al-Mg-Zr alloy is addressed. Mechanical property data demonstrated that as-rolled material was capable of superplastic response without further treatment. Further, superplastic ductility at 300 C was enhanced by a factor of five by increasing the reheating time between rolling passes during processing also at 300 C. This enhanced ductility was associated with a Cu-texture and a microstructure consisting of predominantly high-angle boundaries. Processing to minimize recovery resulted in a strong Brass-texture component, a predominantly low-angle boundary microstructure and poorer ductility.

Hales, S. J.↗

DOE OSTI2020

Materials Data on Mg16ZrAl12 by Materials Project

Mg16ZrAl12 is gamma-brass-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are ten inequivalent Mg sites. In the first Mg site, Mg is bonded in a 10-coordinate geometry to three Mg, one Zr, and six Al atoms. There are two shorter (3.05 Å) and one longer (3.16 Å) Mg–Mg bond lengths. The Mg–Zr bond length is 3.05 Å. There are four shorter (3.08 Å) and two longer (3.14 Å) Mg–Al bond lengths. In the second Mg site, Mg is bonded in a 1-coordinate geometry to four Mg and twelve Al atoms. There are two shorter (3.11 Å) and one longer (3.18 Å) Mg–Mg bond lengths. There are a spread of Mg–Al bond distances ranging from 3.12–3.31 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.09–3.20 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.17 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to four Mg, one Zr, and six Al atoms. Both Mg–Mg bond lengths are 3.02 Å. The Mg–Zr bond length is 3.49 Å. There are a spread of Mg–Al bond distances ranging from 3.05–3.14 Å. In the fifth Mg site, Mg is bonded in a 12-coordinate geometry to six Mg, one Zr, and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.06–3.17 Å. The Mg–Zr bond length is 3.12 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.24 Å. In the sixth Mg site, Mg is bonded in a 12-coordinate geometry to six Mg, one Zr, and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.10–3.17 Å. The Mg–Zr bond length is 3.17 Å. There are a spread of Mg–Al bond distances ranging from 2.90–3.21 Å. In the seventh Mg site, Mg is bonded in a 3-coordinate geometry to eight Mg and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.15–3.42 Å. There are a spread of Mg–Al bond distances ranging from 2.89–3.15 Å. In the eighth Mg site, Mg is bonded in a 10-coordinate geometry to five Mg and six Al atoms. There are one shorter (3.03 Å) and one longer (3.07 Å) Mg–Mg bond lengths. There are a spread of Mg–Al bond distances ranging from 3.03–3.16 Å. In the ninth Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. The Mg–Mg bond length is 3.12 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.24 Å. In the tenth Mg site, Mg is bonded in a 12-coordinate geometry to six Mg, one Zr, and five Al atoms. The Mg–Zr bond length is 3.20 Å. There are a spread of Mg–Al bond distances ranging from 2.87–3.18 Å. Zr is bonded in a 12-coordinate geometry to eight Mg and five Al atoms. There are a spread of Zr–Al bond distances ranging from 2.88–3.03 Å. There are seven inequivalent Al sites. In the first Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. There are one shorter (2.70 Å) and two longer (2.79 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 10-coordinate geometry to seven Mg, one Zr, and three Al atoms. Both Al–Al bond lengths are 2.77 Å. In the third Al site, Al is bonded in a 11-coordinate geometry to seven Mg, one Zr, and three Al atoms. There are a spread of Al–Al bond distances ranging from 2.67–2.79 Å. In the fourth Al site, Al is bonded in a 11-coordinate geometry to seven Mg, one Zr, and three Al atoms. There are one shorter (2.72 Å) and one longer (2.74 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. There are one shorter (2.68 Å) and one longer (2.76 Å) Al–Al bond lengths. In the sixth Al site, Al is bonded in a distorted q6 geometry to eight Mg and three Al atoms. The Al–Al bond length is 2.72 Å. In the seventh Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms.

36 MATERIALS SCIENCE↗