Ultrahigh specific strength in a magnesium alloy strengthened by spinodal decomposition

Strengthening of magnesium (Mg) is known to occur through dislocation accumulation, grain refinement, deformation twinning, and texture control or dislocation pinning by solute atoms or nano-sized precipitates. These modes generate yield strengths comparable to other engineering alloys such as certain grades of aluminum but below that of high-strength aluminum and titanium alloys and steels. Here, we report a spinodal strengthened ultralightweight Mg alloy with specific yield strengths surpassing almost every other engineering alloy. We provide compelling morphological, chemical, structural, and thermodynamic evidence for the spinodal decomposition and show that the lattice mismatch at the diffuse transition region between the spinodal zones and matrix is the dominating factor for enhancing yield strength in this class of alloy.

Automated summary

Magnesium alloys can be strengthened through various methods such as dislocation accumulation, grain refinement, deformation twinning, and spinodal decomposition. The spinodal strengthened ultralightweight Mg alloy in this study achieves specific yield strengths surpassing almost every other engineering alloy, with lattice mismatch at the diffuse transition region between spinodal zones and matrix being the dominating factor for enhancing yield strength.