The study investigates the influence of adding trace alloying elements titanium (Ti), vanadium (V), and zirconium (Zr) on the microstructure and mechanical properties of a new high-strength and heat-resistant piston alloy based on casting ZL109 piston alloy. Mechanical properties of alloy castings with different alloy element contents are characterized using Brinell hardness and tensile performance, while the microstructure is observed using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The findings from orthogonal experimental main effect analysis are as follows: Titanium (Ti) has the greatest influence on alloy hardness, with the highest average hardness achieved at a titanium content of 0.2%; Zirconium (Zr) has the most significant impact on the mechanical properties of the alloy, with a 0.1% zirconium content substantially increasing the alloy’s tensile strength and yield strength; Vanadium (V) has a minor effect on alloy hardness and mechanical properties. Fracture analysis of tensile specimens indicates that the alloy exhibits quasi-cleavage fracture (brittle fracture) at room temperature, displaying typical brittle fracture characteristics.
