Softening Kinetics in Nb-Microalloyed TRIP Steels with Increased Mn Content
Two 5Mn-1.5Al TRIP steels with and without Nb microaddition were developed in the present study. The steels contain bainite, martensite, interlath retained austenite and martensite- austenite islands. The paper presents the results of the compression tests carried out at various temperatures using the Gleeble simulator. To analyze the kinetics of static recrystallization in these steels, a softening kinetics were determined in a double-hit compression test. It was found that the dynamic recovery is a main thermally activated process occurring during hot deformation. The Nb microalloyed steel has higher flow stresses and peak strains than the Nb-free steel. A solute drag effect of Nb results in a slower softening kinetics of Nb containing steel. The effects of Mn on the retardation of Nb(C,N) precipitation and hot deformation characteristics are also discussed.
A. Grajcar and R. Kuziak, "Softening Kinetics in Nb-Microalloyed TRIP Steels with Increased Mn Content", Advanced Materials Research, Vols. 314-316, pp. 119-122, 2011