含Al过共析钢温变形过程中的渗碳体球化

he effect of aluminum on the spheroidization of cementite and the formation of ultrafine (α+θ) microstructure of hypereutectoid steel during warm deformation was investigated by uniaxial hot compression simulation experiment. The results indicated that ultrafine (α＋θ) microduplex microstructures were formed by warm deformation. During warm deformation, the diffusion of carbon and iron atoms were impeded with the addition of Al, the spheroidization of lamellar cementite and the coarsening of cementite particles was retarded as well as the re-pricipitation of cementite particles in ferrite matrix was restricted, resulting a more ultrafine (α＋θ) microduplex microstructure.