Synergizing mechanical properties and damping capacities in a lightweight Al-Zn-Li-Mg-Cu alloy

Li R.; Wilde G.; Zhang Y.

Abstract

Alloys with synergized strength and damping capacity are in urgent need to eliminate vibrations and noises. Herein, a lightweight Al-Zn-Li-Mg-Cu alloy which exhibits similar strengths as traditional high-strength Al alloys and considerable damping capacities is developed. The resulting microstructures and precipitation behaviors are systematically characterized in the hot-rolled and cold-rolled alloy. Meanwhile, damping properties at low temperatures and high temperatures are thoroughly studied. Two rolled alloys show the same multi-segment characteristics, in which the effects of the strain amplitude and high temperature on tanφ are attributed to dislocation pinning and grain boundary viscoelastic sliding, respectively. The damping properties and low density, together with superb mechanical properties, demonstrate their practical application where noise and vibrations must be reduced.