Superstrength of nanograined steel with nanoscale intermetallic precipitates transformed from shock-compressed martensitic steel

Authors

Hai Liang Yu, University of WollongongFollow
Ming Yan, South University of Science and technology of China
Cheng Lu, University of WollongongFollow
Anh Kiet Tieu, University of WollongongFollow
Hui Jun Li, University of WollongongFollow
Qiang Zhu, University of WollongongFollow
Ajit R. Godbole, University of WollongongFollow
Jintao Li, University of WollongongFollow
Lihong Su, University of WollongongFollow
Charlie Kong, University of New South Wales

RIS ID

111114

Publication Details

Yu, H., Yan, M., Lu, C., Tieu, A. K., Li, H., Zhu, Q., Godbole, A., Li, J., Su, L. & Kong, C. (2016). Superstrength of nanograined steel with nanoscale intermetallic precipitates transformed from shock-compressed martensitic steel. Scientific Reports, 6 36810-1-36810-7.

Abstract

An increasing number of industrial applications need superstrength steels. It is known that refined grains and nanoscale precipitates can increase strength. The hardest martensitic steel reported to date is C0.8 steel, whose nanohardness can reach 11.9 GPa through incremental interstitial solid solution strengthening. Here we report a nanograined (NG) steel dispersed with nanoscale precipitates which has an extraordinarily high hardness of 19.1 GPa. The NG steel (shock-compressed Armox 500T steel) was obtained under these conditions: high strain rate of 1.2 μs⁻¹, high temperature rise rate of 600 Kμs⁻¹ and high pressure of 17 GPa. The mean grain size achieved was 39 nm and reinforcing precipitates were indexed in the NG steel. The strength of the NG steel is expected to be ~3950 MPa. The discovery of the NG steel offers a general pathway for designing new advanced steel materials with exceptional hardness and excellent strength.