Multiphase field modeling of austenite to pearlite–ferrite transformation in hypoeutectoid steel

• Increasing cooling rate from 1.0 to 7.0°C/s reduces ferrite proportion from 52vol% to 22vol% at 400°C and refines pearlite lamellae spacing from 1.01 to 0.67 μm at 660°C. • Decreasing prior austenite grain size from 25.23 to 8.92 μm enhances phase transformation driving force, leading to finer pearlite clusters and proeutectoid ferrite. • Raising carbon content from 0.22wt% to 0.37wt% lowers phase transition temperature from 795 to 750°C, increases pearlite proportion from 27vol% to 61vol% at 500°C, and refines pearlite spacing from 1.25 to 0.87 μm at 600°C. • Multiphase field modeling provides a comprehensive understanding of austenite decomposition kinetics and elemental diffusion, aiding in optimizing processing conditions for hypoeutectoid steels.