Dynamic deformation behaviour of 0.51C–1.72Si–0.83Mn–0.56Co high-strength steel

Abstract

In this paper, high-strength steel is prepared by different heat-treatment processes. Through split Hopkinson pressure bar experiment, optical microscope, scanning electron microscope and X-ray diffractometer, the microstructure evolution and mechanical behaviour under high strain rate were studied. The results show that the samples prepared by the two-step isothermal method have the highest compressive strength under the same strain rate, especially at 5000 s⁻¹, the highest can reach 2097 MPa. The retained austenite undergoes transformation under high strain rate conditions, which improves the plastic deformation ability of the material. Compared with the one-step isothermal heat-treatment process, the two-step isothermal heat-treatment process can better control the strength and plasticity under high strain rate deformation conditions.

KEYWORDS:

• ultrafine bainitic steel
• dynamic deformation
• microstructure evolution
• work-hardening
• adiabatic shear

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

The processed data required to reproduce these findings cannot be shared at this time as the data also form part of an ongoing study.

Additional information

Funding

This work was supported by Science and Technology Project of Jiangxi Provincial Department of Education [Grant Number GJJ180439].