Abstract
Transformation-induced plasticity (TRIP) high-entropy alloys (HEAs) have drawn great attention as they present excellent mechanical properties, and their phase stability is critical for the underlying deformation mechanisms and the application temperature range. In this study, the kinetic phase transformation behavior of a dual-phase TRIP-HEA Fe50Mn30Co10Cr10 (at. %) was probed by in situ neutron diffraction during thermal cycling between 293 and 425 K. Continuous austenitic and martensitic transformation were visualized through the evolution of hexagonal close-packed phase fraction during thermal cycling. Specifically, thanks to the magnetic sensitivity of neutron diffraction, it was found that the martensitic transformation under cooling became suppressed when the antiferromagnetic ordering started at ∼326 K. This temperature was further confirmed as the Néel temperature by magnetization measurements. Thermodynamic calculations revealed that the suppression effect on martensitic transformation is attributed to the consumption of the chemical driving force by the magnetic ordering. The magnetic ordering at such relatively high temperature is associated with the high Mn content. These findings shed light on a potential strategy to achieve better mechanical properties of Mn-containing alloys by manipulating the magnetic property through tuning the Mn content.
| Original language | English |
|---|---|
| Article number | 171906 |
| Journal | Applied Physics Letters |
| Volume | 119 |
| Issue number | 17 |
| DOIs | |
| State | Published - Oct 25 2021 |
Funding
Neutron scattering experiments were carried out at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). Microscopy experiments were performed at the Center for Nanophase Materials Sciences (CNMS) at ORNL. SNS and CNMS are national user facilities at ORNL sponsored by the Scientific User Facilities Division, BES, DOE. The authors gratefully thank Dr. Hongbin Bei for providing the tested material. S.F. is grateful to the financial support from China Scholarship Council for her visit at SNS, ORNL. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S.