Precipitation strengthening in an ultralight magnesium alloy.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30824695.
- Also identified by DOI 10.1038/s41467-019-08954-z and PMC identifier 6397269.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Body-centred cubic magnesium-lithium-aluminium-base alloys are the lightest of all the structural alloys, with recently developed alloy compositions showing a unique multi-dimensional property profile. By hitherto unrecognised mechanisms, such alloys also exhibit exceptional immediate strengthening after solution treatment and water quenching, but strength eventually decreases during prolonged low temperature ageing. We show that such phenomena are due to the precipitation of semi-coherent D0<sub>3</sub>-Mg<sub>3</sub>Al nanoparticles during rapid cooling followed by gradual coarsening and subsequent loss of coherency. Physical explanation of these phenomena allowed the creation of an exceptionally low-density alloy that is also structurally stable by controlling the lattice mismatch and volume fraction of the Mg<sub>3</sub>Al nanoparticles. The outcome is one of highest specific-strength engineering alloys ever developed.