Abstract
The alloy-design strategy of combining multiple elements in near-equimolar ratios has shown great potential for producing exceptional engineering materials, often known as 'high-entropy alloys'. Understanding the elemental distribution, and, thus, the evolution of the configurational entropy during solidification, is undertaken in the present study using the Al1.3CoCrCuFeNi model alloy. Here we show that, even when the material undergoes elemental segregation, precipitation, chemical ordering and spinodal decomposition, a significant amount of disorder remains, due to the distributions of multiple elements in the major phases. The results suggest that the high-entropy alloy-design strategy may be applied to a wide range of complex materials, and should not be limited to the goal of creating single-phase solid solutions.
| Original language | English |
|---|---|
| Article number | 5964 |
| Journal | Nature Communications |
| Volume | 6 |
| DOIs | |
| State | Published - Jan 20 2015 |
Funding
Dr Ashfia Huq, Instrument Scientist at the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS), provided valuable instruction and guidance in the neutron diffraction data reduction and analyses. Dr Michael K. Miller, of the ORNL Materials Science and Technology Division, conducted APT studies. SNS scientific associates, John Carruth and Luke Heroux, provided expert technical assistance during the neutron experiments. SNS Sample Environment technicians, Bruce Hill and Cory Fletcher, played a major role in the development and set up of the aerodynamic sample levitator. Dr Lawrie Skinner and engineer, Ms Sonia Tumber, of Materials Development, Inc. (MDI), had key roles in the development of the levitator and set up of the neutron experiments. The instruction and guidance for conducting the high-energy synchrotron X-ray diffraction studies was given by Professor Wojciech Dmouski of The University of Tennessee and Dr Douglas Robinson of the Advanced Photon Source, Argonne National Laboratory. Professor Michael Widom at Carnegie Mellon University provided useful discussions on AIMD simulations. Neutron scattering and microscopy experiments were conducted at ORNL, through user programs at the SNS and Center for Nanophase Materials Sciences (CNMS) facilities, respectively, which are sponsored by the Office of Basic Energy Sciences, US Department of Energy under contract DE-AC05-00OR22725 with UT-Battelle, LLC. The synchrotron X-ray diffraction research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under contract no. DE-AC02-06CH11357. The development of the aerodynamic levitator system was supported by DOE grant number DE-SC0004684. The present research was performed in support of the Innovative Processing and Technologies Program of the National Energy Technology Laboratory’s (NETL) Strategic Center for Coal under the Research and Engineering Services (RES) contract DE-FE-0004000. Partial computing support was provided under The Extreme Science and Engineering Discovery Environment (XSEDE) Award No. DMR120048. The National Science Foundation (DMR-0909037, CMMI-0900291 and CMMI-1100080), the Department of Energy (DOE) Office of Nuclear Energy’s Nuclear Energy University Programs (NEUP, grant #00119262) and the DOE Office of Fossil Energy, NETL (DE-FE0008855 and DE-FE-0011194), with Drs C.V. Cooper, A. Ardell, Z.M. Taleff, R.O. Jenseng Jr, L. Tian, V. Cedro, S. Lesica and S. Markovich as program managers, provided additional funding, particularly for P.K.L. (NSF) and the student (Z.T., DOE) at The University of Tennessee. P.K.L. very much appreciates the support from the U.S. Army Office Project (W911NF-13-1-0438) with the program manager, Dr S.N. Mathaudhu. This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, product or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process or service by trade name, trademark, manufacturer or otherwise does not necessarily constitute or imply its endorsement, recommendation or favouring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.
| Funders | Funder number |
|---|---|
| DOE Office of Science | |
| Extreme Science and Engineering Discovery Environment | |
| National Energy Technology Laboratory | DE-FE-0004000 |
| Nuclear Energy University Programs | 00119262 |
| Office of Basic Energy Sciences | |
| US Department of Energy | DE-AC05-00OR22725 |
| XSEDE | |
| National Science Foundation | CMMI-1100080, CMMI-0900291, DMR-0909037 |
| U.S. Department of Energy | |
| Office of Fossil Energy | DE-FE-0011194, DE-FE0008855 |
| Office of Science | |
| Office of Nuclear Energy | |
| Argonne National Laboratory | DE-SC0004684 |
| U.S. Army | W911NF-13-1-0438 |
| University of Tennessee |