Abstract: Since phosphor bronze cannot be strengthened by heat treatment, improving the as-cast microstructure and properties is of great significance. In this study, solidification experiments with different rotating magnetic field (RMF) parameters were designed to investigate their effects on the microstructure and properties of phosphor bronze. The experimental results show that, at a current intensity of 120 A, an unprecedented grain refinement effect is achieved. Additionally, the strength-ductility synergy and homogeneous deformation are achieved due to grain refinement. The mechanism of grain refinement was analyzed based on microstructural morphology and the solidification process. Moreover, the positive effect of the wide liquidus-solidus interval on grain refinement was discovered. The grain refinement effect induced by RMF benefits the processing and performance improvement of phosphor bronze with a wide liquidus-solidus interval. This work provides new insights for the strengthening and processing of phosphor bronze and potentially other metals.

Key words: Rotating magnetic field, Grain refinement, Strength-ductility synergy, Homogeneous deformation, Phosphor bronze