Influence of Nb, V and Ti on peak strain of deformed austenite in Mo-based micro-alloyed steels

摘要

In this paper, the influence of Nb, Vand Ti on the peak strain of deformed austenite in Mo-based micro-alloyed steels has been studied. Four steels, identified as Mo, Mo + V, Mo + Nb and Mo + Ti, respectively, were heated to 1200°C and held for 10 min and then the temperature was rapidly reduced to test temperatures and maintained for 40 s. The test temperatures were 950,1000,1050, 1100, 1150 and 1200°C at the strain rates of 0.05, 0.1, 0.5, 1 and 5 s~(-1), respectively. Results indicate that the presence of Nb, Ti, and V affects significantly the value of peak strain (ε_p), especially Nb which has a significant effect on the start of the dynamic recrystallisation. For all the steels studied, the peak strain ε_p was modelled as a function of the Zener-Hollomon parameter and the austenite grain size.