A Novel In Situ (Al3Ni + Al3Ti)/Al Composite Inoculant and Its Effects on the Microstructure, Damping and Mechanical Properties of Zn–Al Eutectoid Alloy

A novel in situ (Al 3 Ni + Al 3 Ti)/Al composite inoculant was fabricated, and its effects on the microstructure, damping and mechanical properties of the Zn–Al eutectoid alloy (ZA22) were systematically studied. It was found that due to the unique combined effect of Al 3 Ni and Al 3 Ti particles, the novel inoculant had an efficient refining effect on the ZA22 alloy. When 0.6 wt pct inoculant was added, the best refining effect was achieved, and the average size of the α phase in the ZA22 alloy could be reduced to 10 μ m (0.1 times that of the original ZA22 alloy). Compared with the original ZA22 alloy, the tensile strength, elongation, Vickers hardness and damping at high temperatures of the inoculated ZA22 alloy with the best refining effect were increased by 19, 264, 27 and 80 pct, respectively, whereas the damping at low temperatures was reduced by 50 pct. Based on in depth microscopic observation, correlated mechanisms were discussed in detail. This study can provide ideas and theoretical basis for the design of novel inoculants and the fabrication of high damping alloys with excellent mechanical properties. Graphical Abstract