Deformation mechanism transition in Fe–17Mn–0.4C–0.06V TWIP steel with different strain rates

ABSTRACT

The dynamic tensile behaviour and deformation mechanism of the Fe–17Mn–0.4C–0.06V twinning-induced plasticity (TWIP) steel were investigated over a wide range of strain rates from 10⁻⁴ to 10³ s⁻¹. With increasing strain rate, the stacking fault energy increased due to the increase of adiabatic heating temperature, ΔT. At 10⁻⁴ to 10¹ s⁻¹, the transformation-induced plasticity (TRIP) effect coexisted with the TWIP effect and weakened with increasing strain rate. With the increase of strain rate in the range of 10⁻¹ to 10¹ s⁻¹, the TWIP effect strengthened gradually and intersected deformation twins were formed. When the strain rate was higher than 10¹ s⁻¹, the TRIP effect disappeared and the twinning was inhibited since the adiabatic heating effect elevated.

KEYWORDS:

• TWIP steel
• deformation mechanism
• strain rate
• strain-induced martensite transformation
• mechanical twinning
• adiabatic heating

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors thank the financial support of the National Natural Science Foundation of China (grant No. 51371032) and the State Key Research and Development Program of China (grant No. 2016YFB0101605).