journal article·2021-05

Microstructure, mechanical properties and oxidation behavior of NbTaTi and NbTaZr refractory alloys

O.N. Senkov, J. Gild, T.M. Butler

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Abstract

Abstract This study reports the microstructure, phase composition, mechanical properties and oxidation behavior of NbTaTi and NbTaZr ternary equiatomic alloys. These ternary components, together with earlier reported NbTiZr and MoNbTi, are commonly observed in refractory high entropy alloys (RHEAs) with a single-phase BCC or multi-phase crystal structures. Therefore, the reported information about these ternary alloys is thought to be useful for the development of advanced RHEAs. While NbTiZr and MoNbTi are single-phase BCC structures, NbTaTi and NbTaZr are multi-phase alloys. NbTaTi consists of a BCC matrix and discontinuous, Ti-rich precipitates with BCC and FCC crystal structures. NbTaZr consists of a co-continuous spinodal mixture of two BCC phases, one of which is rich in Ta and Nb and another is rich in Zr, and it also contains a Zr-rich HCP phase in the form of coarse grain-boundary particles. NbTaTi has compression yield stress of 724 MPa at 25 °C, 268 MPa at 800 °C and 129 MPa at 1200 °C. NbTaZr is stronger, with the compression yield stress of 1027 MPa at 25 °C, 530 MPa at 800 °C and 183 MPa at 1200 °C. Both alloys show rapid oxidation with formation of complex oxides during holding at 1200 °C.
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Research context

OpenAlex topics: High Entropy Alloys Studies · High-Temperature Coating Behaviors · Intermetallics and Advanced Alloy Properties

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (54)

Show source-provided references
1. A critical review of high entropy alloys and related concepts
2. Mapping the world of complex concentrated alloys
3. Development and exploration of refractory high entropy alloys: a review
4. High temperature strength of refractory complex concentrated alloys
5. Accelerated exploration of multi-principal element alloys for structural applications
6. Compositional effect on microstructure and properties of NbTiZr-based complex concentrated alloys
7. CALPHAD-aided development of quaternary multi-principal element refractory alloys based on NbTiZr
8. New ternary equi-atomic refractory medium-entropy alloys with tensile ductility: Hafnium versus titanium into NbTa-based solution
9. Exceptional damage-tolerance of a medium-entropy alloy crconi at cryogenic temperatures
10. Temperature dependence of the mechanical properties of equiatomic solid solution alloys with face-centered cubic crystal structures
11. In situ lift-out dedicated techniques using FIB-SEM system for TEM specimen preparation
12. Ductile Nb alloys with reduced density and cost
13. Lattice parameters, thermal expansions, and Grüneisen coefficients of Zirconium, 4.2 to 1130 K
14. Powder Diffraction File 01–073-9894 (Zirconium Oxide, Zr2O), International Center for Diffraction Data, Newtown Square, PA, USA, 2020.
15. Powder Diffraction File 04–003-6336 (Zirconium Oxide, ZrO), International Center for Diffraction Data, Newtown Square, PA, USA, 2020.
16. Powder Diffraction File 04–013-3441 (Zirconium Oxide, O2Zr), International Center for Diffraction Data, Newtown Square, PA, USA, 2020.
17. The N-Ti (nitrogen-titanium) system
18. Microstructure and properties of Nb-Mo-Zr based refractory alloys
19. Williams · 1996
20. The O-Zr (oxygen-zirconium) system
21. Thermodynamic evaluation of the Nb-O-Zr system
22. The N-Zr (nitrogen-zirconium) system
23. Effect of Fe additions on the microstructure and properties of Nb-Mo-Ti alloys
24. Butler · 2020
25. High temperature oxidation behaviors of equimolar NbTiZrV and NbTiZrCr refractory complex concentrated alloys (RCCAs)
26. Accelerated oxidation in ductile refractory high-entropy alloys
27. Oxidation mechanism of Nb–Si-based ultra-high temperature materials
28. High-temperature oxidation of β-NbTi alloys
29. Phase diagram at low temperature of the system ZrO2/Nb2O5
30. Oxides formed between ZrO2 and Nb2O5
31. Compound and solid-solution formation, phase equilibria and electrical properties in the ceramic system ZrO2–La2O3 –Ta2O5
32. Effect of oxide additions on polymorphism of tantalum pentoxide (system Ta2O5-TiO2)
33. The O-Ta (Oxygen-Tantalum) system
34. A simplified model connecting lattice distortion with friction stress of Nb-based equiatomic high entropy alloys
35. Microstructure and elevated temperature properties of a refractory TaNbHfZrTi alloy
36. Microstructure and room temperature properties of a high-entropy TaNbHfZrTi alloy
37. Enhanced mechanical properties of HfMoTaTiZr and HfMoNbTaTiZr refractory high-entropy alloys
38. AFLOW: an automatic framework for high-throughput materials discovery
39. AFLOWLIB.ORG: a distributed materials properties repository from high-throughput ab initio calculations
40. Evaluation of the tantalum-titanium phase diagram from ab-initio calculations
41. Okamoto · 2010
42. Villars · 1995
43. The O-Ti (oxygen-titanium) system
44. Rolling-induced face centered cubic Titanium in hexagonal close packed titanium at room temperature
45. Formation of face-centered-cubic titanium by mechanical attrition
46. Face-centered-cubic titanium − a new crystal structure of Ti in a Ti-8Mo-6Fe alloy
47. Phase transformations in Niobium 16 to 40% zirconium alloys above the monotectoid temperature
48. Phase transformations. Examples from titanium and zirconium alloys
49. Development of a refractory high entropy superalloy
50. Characterization of the microstructure of the compositionally complex alloy AlMo0.5NbTa0.5TiZr
51. Phase stability as a function of temperature in a refractory high-entropy alloy
52. Elucidating the microstructural development of refractory metal high entropy superalloys via the TiTaZr constituent system
53. Effects of Mo, Nb, Ta, Ti, and Zr on mechanical properties of equiatomic Hf-Mo-Nb-Ta-Ti-Zr alloys
54. Calculations of parabolic rate constants for metal oxidation