Ce微合金化对25CrMoV钢连续冷却组织转变行为的影响OA

The phase transformation points and continuous cooling transformation(CCT)curves of 25CrMoV test steels without Ce and with 0.007 6%Ce content are determined via relevant tests,and the room temperature microstructures of the two test steels are observed under different cooling speeds,and their hardness is measured.The analysis results show that the rare earth Ce alloying reduces the temperatures at Ac1,Ar1 Points of the 25CrMoV test steel,whereas increases the temperatures of Ac3,Ar3,Ms and Mf Points;and the addition of rare earth Ce expands both the F﹢P transformation zone and the B transformation zone,and shifts the F﹢P transformation zone to the right;when the continuous cooling rate is≥10℃/s,the microalloying of rare earth Ce reduces the M transformation zone,and inhibits the transformation of M;when the continuous cooling rate is within the range of 1.0～40℃/s,the hardness of the 25CrMoV test steel with rare earth Ce is significantly higher than that of 25CrMoV test steel without Ce.