Ultrafine-grained Mg-Gd-Ag alloy

Solute-cluster strengthening

Grain boundary stabilization and solute cluster formation provide additional strengthening in ultrafine-grained Mg alloys, circumventing the weak age-hardening bottleneck.

Yang, Zhenquan · Ma, Aibin · Jiang, Jinghua · Xu, Bingqian · Sun, Jiapeng

Journal of Alloys and Compounds 2026

Specifications

Hardness increment after aging

{'zh': '2.6', 'en': '2.6'} HV

Yield strength increment after aging

{'zh': '38', 'en': '38'} MPa

Strength contribution from grain boundary stabilization

{'zh': '22', 'en': '22'} MPa

Strength contribution from solute clusters

{'zh': '32', 'en': '32'} MPa

Average grain size

{'zh': '0.92', 'en': '0.92'} μm

Advantages

Strength still increases

Despite the weak age-hardening response, yield strength increases by 38 MPa after aging due to grain boundary stabilization and solute cluster formation.

Strengthening sources identified

The contributions of grain boundary stabilization (22 MPa) and solute clusters (32 MPa) are quantitatively separated, guiding future optimization.

Applications

• High-strength Mg alloys：Aging adds extra strengthening to ultrafine-grained Mg alloys for lightweight load-bearing parts.
• Lightweight structural materials：Strength is enhanced while retaining low density, meeting weight-reduction demands in aerospace and transportation.
• Ultrafine-grained metals：The aging behavior of ultrafine-grained Mg alloys is clarified, guiding the synergistic design of grain refinement and precipitation strengthening.