Abstract
In the present study, the phase evolution and microstructure of CrMoNbTiW, a new equi-atomic refractory high-entropy alloy, are studied. The alloy was synthesized through mechanical alloying (MA) followed by consolidation using spark plasma sintering. After MA, a major BCC solid solution along with residual Cr and Nb were observed. However, secondary phases such as Laves and carbides were also observed in addition to the major BCC solid solution after sintering. Unsolicited contamination from the milling media is found to be one of the reasons for the formation of secondary phases. The high hardness of 8.9 GPa after sintering was attributed to the presence of secondary phases along with the nanocrystalline nature of the alloy. To understand the phase evolution, calculation of phase diagram was carried out using CALPHAD. Further, binary phase diagram inspection and simple empirical parameters were also used to assess their effectiveness in predicting phases.
| Original language | English |
|---|---|
| Pages (from-to) | 756-766 |
| Number of pages | 11 |
| Journal | Journal of Materials Research |
| Volume | 34 |
| Issue number | 5 |
| DOIs | |
| State | Published - Mar 14 2019 |
| Externally published | Yes |
Funding
The authors thank ISRO-IITM cell for the financial support through the project ICSR/ISRO-IITM/MET/13-14/150/BSMT. The authors are grateful to Ms. Dilpreet Danjal (former B.Tech student, NIT Rourkela), Mr. Adil Shaik (MS scholar, IIT Madras), Mr. G. Karthick, Mr. N.T.B.N. Koundinya, Dr. Soumya Sridar (Ph.D. students, Department of Metallurgical and Materials Engineering at IIT Madras) and Dr. Niraj Chawake (former Ph.D. student, Department of Metallurgical and Materials Engineering at IIT Madras) for their valuable suggestions and discussion. The authors thank NFAPT team for their assistance in the EBSD analysis.
| Funders | Funder number |
|---|---|
| IIT Madras | |
| National Institute of Technology Rourkela |
Keywords
- mechanical alloying
- second phases
- sintering