Frank M, Nene S S, Chen Y, Gwalani B, Kautz E J, Devaraj A, An K, Mishra R S
Department of Materials Science and Engineering, University of North Texas, Denton, TX, 76207, USA.
Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Jodhpur, 342037, India.
Sci Rep. 2020 Dec 17;10(1):22263. doi: 10.1038/s41598-020-79492-8.
Transformation induced plasticity (TRIP) leads to enhancements in ductility in low stacking fault energy (SFE) alloys, however to achieve an unconventional increase in strength simultaneously, there must be barriers to dislocation motion. While stacking faults (SFs) contribute to strengthening by impeding dislocation motion, the contribution of SF strengthening to work hardening during deformation is not well understood; as compared to dislocation slip, twinning induced plasticity (TWIP) and TRIP. Thus, we used in-situ neutron diffraction to correlate SF strengthening to work hardening behavior in a low SFE FeMnCrCoSi (at%) high entropy alloy, SFE ~ 6.31 mJ m. Cooperative activation of multiple mechanisms was indicated by increases in SF strengthening and γ-f.c.c. → ε-h.c.p. transformation leading to a simultaneous increase in strength and ductility. The present study demonstrates the application of in-situ, neutron or X-ray, diffraction techniques to correlating SF strengthening to work hardening.
相变诱发塑性（TRIP）可提高低堆垛层错能（SFE）合金的延展性，然而，要同时实现强度的非常规提高，必须存在位错运动的障碍。虽然堆垛层错（SFs）通过阻碍位错运动有助于强化，但与位错滑移、孪生诱发塑性（TWIP）和TRIP相比，SF强化对变形过程中加工硬化的贡献尚未得到很好的理解。因此，我们使用原位中子衍射来关联SF强化与低SFE FeMnCrCoSi（原子百分比）高熵合金（SFE约为6.31 mJ/m）中的加工硬化行为。SF强化和γ-面心立方→ε-六方密堆结构转变的增加表明多种机制的协同激活，从而导致强度和延展性同时增加。本研究展示了原位中子或X射线衍射技术在关联SF强化与加工硬化方面的应用。
