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The continuous cooling transformation process and the organization performance of transformation product was investigated by means of dilatation test during single pass deformation on Gleeble-3500. The result shows that bainite transition can be happened when the cooling speed about 3??/s on 460B steel with boron, and the grain size is coarse and hardness is higher when the cooling speed (0. 1, 0. 3, 0. 5??/s)is slowly, it is more tiny than without boron. Boron can make the CCT curves shift to right, the transition from austenite to ferrite and pearlite is restrained, the hardenability of the steel are obviously improved, the cooling speed from austenite to martensite is lower and Ac3, Ac1, Ar3, Ar1, Ms is dropped.