Effect of gradient temperature rolling process on precipitation behavior in Q690D steel

Abstract In this paper, the second phase precipitation model is incorporated into finite element simulation system of hot rolling process through secondary development subprogram VUSDFLD ABAQUS, and analysis calculation nucleation rate, volume fraction size precipitates under different temperature fields strain are realized. The size, morphology distribution microalloyed carbonitride in Q690D steel gradient (GTR) uniform (UTR) were studied by laboratory experiments. results show that sites matrix increase GTR, which conducive to new promotes re dissolution large precipitates. Finally, after tempering, precipitate particles distributed randomly on ferrite matrix, refined 20 ∼ 35 nm, resulting obvious strengthening microstructure refining effects.