Ultrafine-Grained Steel Produced by Warm Rolling and Annealing of Lath Martensite
Steel plates with lath martensite microstructure were rolled up to 68% reduction at 673 K and then annealed at 473-973 K. The microstructure evolution was studied by using an optical microscope and a transmission electron microscopy. And the properties were investigated by using tensile tests and hardness tests. Results show that ultrafine grains + nano-carbides are obtained in the steel plates. The specimen annealed at 823 K has a good combination of strength and ductility. The tensile strength and total elongation are 1028 MPa and 7.2%, respectively. And the hardness is 338 Hv.
Jing Tao Wang, Roberto B. Figueiredo and Terence G. Langdon
X. Zhao and X. L. Yang, "Ultrafine-Grained Steel Produced by Warm Rolling and Annealing of Lath Martensite", Materials Science Forum, Vols. 667-669, pp. 863-866, 2011