Determination of no-recrystallization temperature for a Nb-bearing steel

Abstract

The recrystallization behavior of a Nb-bearing steel was investigated during multipass deformation under continuous cooling conditions. By a series of six-pass compression tests conducted on a thermomechanical simulator, the effect of deformation parameters, including strain, strain rate and interpass time, on the no-recrystallization temperature (T _nr) was determined. The results show that T _nr decreases with increasing strain and also decreases slightly with increasing strain rate. The strain has more appreciable influence on the T _nr compared with strain rate. When the interpass time is less than 10 s, the T _nr decreases with increasing interpass time. The mathematical model of T _nr was established considering the effect of pass strain, strain rate and interpass time. The calculated results agreed well with the actual experimental value.

Keywords

Nb-bearing steel / recrystallization / no-recrystallization temperature / deformation parameters

References

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