Effect of Trace Amount Modified SiC Nanoparticles on Microstructures and Mechanical Properties of ZA27 Alloy

In order to modify the microstructure and enhance the mechanical properties, the influence of trace amount modified SiC nanoparticles on the as‐cast ZA27alloy is investigated. The results indicate that the original coarse and developed dendrites are refined gradually and turn into fine and uniform equiaxed crystals and spherical structures. The primary α(Al) phases, eutectoid( α + η ) phases, and ε (CuZn 4 ) phases are also refined. The planar disregistry calculations between 6H‐SiC and α (Al) show that 6H‐SiC is an effective heterogeneous nucleus substrate for α (Al). The refined mechanism of modified SiC nanoparticles on ZA27 alloy is also discussed. When the addition is 0.5%, the tensile strength is increased by 6.5% and elongation is increased by 12.7%. The yield strength of SiC nanoparticles reinforced ZA27 is discussed quantitatively to reveal the strengthening mechanisms.