Quenching experiments were performed at different cooling rates under non-directional solidification by differential thermal analysis, and the morphologic variation of primary phase, phase transition temperature and hardness change at the same quenching temperature were investigated. The experimental results show that, with the gradual decrease of the cooling rate from 25 K/min, the morphology of ferrite starts to transform experiencing the dendrite, radial pattern, Widmanstatten-like and wire-net. Sample starts to present the Widmanstatten-like microstructure at 10 K/min which does not exist at higher or lower cooling rates, and this microstructure is detrimental to the mechanical property. Except 10 K/min, the hardness decreases with decreasing cooling rate. Quenching experiments were performed at different cooling rates under non-directional solidification by differential thermal analysis, and the morphologic variation of primary phase, phase transition temperature and hardness change at the same quenching temperature were. The experimental results show that with the gradual decrease of the cooling rate from 25 K / min, the morphology of ferrite starts to transform experiencing the dendrite, radial pattern, Widmanstatten-like microstructure at 10 K / min which does not exist at higher or lower cooling rates, and this microstructure is detrimental to the mechanical property. Except 10 K / min, the hardness decreases with decreasing cooling rate.