Effect of Forging Process on V-Nb-Ti Microalloyed Non-Quenched and Tempered Steels

Abstract

The effect of forging process on microstructure and performance of V-Ti, V-Nb-Ti non-quenched and tempered microalloying steel was investigated in this study. By comparing the characteristics between V-Ti and V-Nb-Ti microalloyed non-quenched and tempered steels by the forging process,the machinsm of micro-alloy technology and forging process for dynamic recrystallization and microstructure refinement was investigated. It revealed that addition of Nb in micro-alloying steel can increase significantly non-recrystallization temperature during forging process, and enhance the V (C, N) precipitation strengthening effect of V-Ti microalloyed non-quenched and tempered steels. V-Nb-Ti microalloying technology and controlling forging temperature in non-recrystallization region, can refine grain size, promote proeutectoid ferrite emerging and pearlite morphology alienating. By controlling final forging temperature in non-recrystallization region, the strength and toughness of V-Nb-Ti micro-alloy non-quenched and tempered steels can be improved.