Microstructure and damping capacity of high-temperature damping ZA27/7075Al composites prepared by friction stir processing

• The river-like reinforced phases form numerous well-bonded interfaces in the FSP-ZA27/7075Al composite. • Internal friction value of the composite is 13.58-fold that of the 7075Al alloy at 300 °C. • The composite shows excellent high-temperature comprehensive damping capacity . • The damping mechanism of the FSP-ZA27/7075Al composite was analyzed. FSP-ZA27/7075Al composites with enhanced high-temperature damping capacity were fabricated using friction stir processing. The interface bonding between the ZA27 and 7075Al alloys is strong, with no apparent defects or new phase formation in the composites. The improved damping capacity and comprehensive damping index of the composites, in comparison to the 7075Al alloy, result from the contributions of grain refinement and the inherent damping capacity of the reinforcement phase. At 300 °C, the internal friction value of the composites is 798 % and 1258 % greater than that of FSP-7075Al and 7075-T651 Al alloys, respectively. At 275 °C, the composites show internal friction peaks similar to those of the ZA27 alloy.