Tuning Cr-rich nanoprecipitation and heterogeneous structure in equiatomic CrFeNi medium-entropy stainless alloys
Kai Wang1, Xue-jiao Wang1, Tuan-wei Zhang2, Xi Jin1, Hui-jun Yang1, Jun-wei Qiao1,3
1 College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China 2 College of Mechanical and Vehicle Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China 3 State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China
Tuning Cr-rich nanoprecipitation and heterogeneous structure in equiatomic CrFeNi medium-entropy stainless alloys
Kai Wang1, Xue-jiao Wang1, Tuan-wei Zhang2, Xi Jin1, Hui-jun Yang1, Jun-wei Qiao1,3
1 College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China 2 College of Mechanical and Vehicle Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China 3 State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China
摘要 High-/medium-entropy stainless alloys (HESAs/MESAs) are a new kind of alloys with great potential to combine excellent properties from high-/medium-entropy alloys (HEAs/MEAs) and stainless steels. A CrFeNi MESA was chosen to investigate its microstructures and mechanical behaviors. After homogenization, the strength and ductility of CrFeNi MESAs with single-phase face-centered-cubic (fcc) structure were higher compared with those of Fe100-x–yCrxNiy austenitic stainless steels. Cr-rich body-centered-cubic (bcc) precipitates and heterogeneous structure were introduced by cold rolling and annealing at 800 °C. Rolling at 700 °C results in higher dislocation density and the occurrence of lamellar Cr-rich bcc precipitates. High-density dislocations and fcc grains with heterogeneous structure, together with Cr-rich bcc precipitates, contribute to a yield strength improvement of about 50 MPa, and appreciable tensile yield strength of ~ 540 MPa and fracture strain of ~ 20% are obtained. It reveals that not only compositional variations but also grain size and phase structure tuning can be utilized for achieving desired mechanical properties.
Abstract：High-/medium-entropy stainless alloys (HESAs/MESAs) are a new kind of alloys with great potential to combine excellent properties from high-/medium-entropy alloys (HEAs/MEAs) and stainless steels. A CrFeNi MESA was chosen to investigate its microstructures and mechanical behaviors. After homogenization, the strength and ductility of CrFeNi MESAs with single-phase face-centered-cubic (fcc) structure were higher compared with those of Fe100-x–yCrxNiy austenitic stainless steels. Cr-rich body-centered-cubic (bcc) precipitates and heterogeneous structure were introduced by cold rolling and annealing at 800 °C. Rolling at 700 °C results in higher dislocation density and the occurrence of lamellar Cr-rich bcc precipitates. High-density dislocations and fcc grains with heterogeneous structure, together with Cr-rich bcc precipitates, contribute to a yield strength improvement of about 50 MPa, and appreciable tensile yield strength of ~ 540 MPa and fracture strain of ~ 20% are obtained. It reveals that not only compositional variations but also grain size and phase structure tuning can be utilized for achieving desired mechanical properties.
Kai Wang,Xue-jiao Wang,Tuan-wei Zhang, et al. Tuning Cr-rich nanoprecipitation and heterogeneous structure in equiatomic CrFeNi medium-entropy stainless alloys[J]. Journal of Iron and Steel Research International, 2022, 29(3): 529-536.
2022, Vol. 29 
