High damping performance of Al-35%Zn alloy achieved through Zirconia phase transformation

High-zinc casting aluminum alloys have unsatisfactory damping capacity and mechanical strength, which severely restricts their application in vibration-sensitive structures. A novel AlZn composite is hereby proposed, which is fortified with 8 wt% yttria-stabilized zirconia (YSZ) nanoparticles and is prepared by means of stirring casting, cold rolling, and heat treatment. The addition of the nano YSZ enhances energy dissipation by exploiting the stress-induced phase transformation of ZrO₂ from tetragonal to monoclinic. Annealing at 350 ℃ further improves the damping performance by promoting recrystallization, Zn precipitation in Al matrix and retaining metastable tetragonal ZrO₂. The tensile strength of the YSZ/AlZn composite is 386 MPa, and the peak elongation is 9.16%. The primary mechanisms for enhancing damping performance include interface sliding at the α and η interface, dislocation motion, and energy absorption induced by phase transformation. This work establishes a scalable strategy for designing lightweight, highly damping metal matrix composites with promising applications in vibration suppression and structural reliability in aerospace, automotive, and precision mechanical systems.