Abstract: Microstructure evolution of 12Cr-F/M steel under different heat treatment processes (heating at 1100-1200 ℃ and holding for 1-2 h) was studied, and hot deformation behavior of the steel under deformation temperature of 800-1000 ℃ and strain rate of 0.01-10 s^-1 was also studied by using thermal simulation compression tests. The results show that as the solution treatment temperature increases, the ferrite grain size in the 12Cr-F/M steel first decreases and then increases. With the prolongation of holding time, the ferrite grains all grow and coarsen. After the solution treatment, some low melting point Laves precipitates in the matrix decompose and dissolve in the matrix, and the total amount gradually reducing. After solution treated at 1150 ℃ for 1 h, the ferrite grain size in the steel matrix is smaller, while the amount of Laves precipitates is less. The flow stress of the 12Cr-F/M steel during high-temperature deformation decreases with increase of the temperature, and increases with increase of the strain rate.

Key words: 12Cr-F/M steel, solution treatment, microstructure, hot deformation