The role of nitrogen in the oxidation behaviour of a Ti6242S alloy: a nanoscale investigation by atom probe tomography
Source abstract
Abstract
When used at high temperature in air, titanium-based alloys form an oxide scale at their surface but also dissolve large amount of oxygen in their metallic matrix and this is a cause of embrittlement. Nitrogen is a secondary oxidant, which also dissolves in and embrittles the alloy. Oxidation experiments of Ti- 6Al-2Sn-4Zr-2Mo-0.1Si titanium-based alloy, for 10 0 0 h at 650 °C in synthetic air (N 2 -20%O 2 ) and in a mixture of Ar-20%O 2 , showed that nitrogen decreases both oxide scale growth and oxygen dissolution. Atom probe tomography was used to investigate the alloy/oxide interface. The results revealed that the nitrogen effect is due to the formation of interfacial layers of oxynitrides and nitride (Ti 2 N), but also to the formation of a nitrogen rich α-titanium-based solid solution, which all act as diffusion barriers for oxygen, because of their low oxygen solubility. A comparison between the experimental results and thermodynamic calculations is also reported.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Advanced Materials Characterization Techniques · Metal and Thin Film Mechanics · Titanium Alloys Microstructure and Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (36)
Show source-provided references
1. Effect of microstructure on oxygen rich layer evolution and its impact on fatigue life during high-temperature application of α/β titanium10.1016/j.actamat.2016.01.058 ↗
2. Effects of three interstitial solutes (nitrogen, oxygen, and carbon) on the mechanical properties of high-purity, alpha titanium10.1007/BF03399001 ↗
3. The effects of the Oxygen-enriched Surface Layer on Mechanical Properties of α+β Type Titanium Alloys10.2355/isijinternational.45.133 ↗
4. Titanium α- nitrogen solid solution formed by high temperature nitriding: diffusion of nitrogen, hardness, and crystallographic parameters10.1007/BF02654379 ↗
5. The role of nitrogen in the oxidation behaviour of titanium and some binary alloys
6. Effect of Nitrogen on the Kinetics of Oxide Scale Growth and of Oxygen Dissolution in the Ti6242S Titanium-Based Alloy
7. A comparison of the high temperature nitridation and oxidation behaviour of metals10.1016/0010-938X(79)90030-1 ↗
8. Defective TiO2 with oxygen vacancies: synthesis, properties and photocatalytic applications10.1039/c3nr00476g ↗
9. Influence of alloying elements on the dissolution of oxygen in the metallic phase during the oxidation of titanium alloys10.1007/BF01233110 ↗
10. Influence of chromium on the oxidation of titanium between 550° and 700°C
11. Influence of silicon on the oxidation of titanium between 550 and 700°C
12. Rakowski · 1993 · 476‑487
13. Mechanism of isothermal oxidation of the intel-metallic TiAl and of TiAl alloys
14. Improving the high temperature oxidation resistance of pure titanium by shot-peening treatments
15. Vande Put, STEM-EELS identification of TiOXNY, TiN, Ti2N and O, N dissolution in the Ti2642S alloy oxidized in synthetic air at 650 °C10.1016/j.corsci.2019.03.037 ↗
16. Graded microstructure and mechanical properties of additive manufactured Ti–6Al–4V via electron beam melting10.1016/j.actamat.2015.06.036 ↗
17. Revealing martensitic transformation and α/β interface evolution in electron beam melting three-dimensional-printed Ti-6Al-4V10.1038/srep26039 ↗
18. On the potential mechanisms of β to α′ + β decomposition in two phase titanium alloys during additive manufacturing: a combined transmission Kikuchi diffraction and 3D atom probe study10.1007/s10853-019-03984-w ↗
19. Precipitation processes in the Beta-Titanium alloy Ti–5Al–5Mo–5V–3Cr10.1016/j.jallcom.2015.05.251 ↗
20. Characterization of yttrium-rich precipitates in a titanium alloy weld10.1016/j.matchar.2016.10.014 ↗
21. Precipitation of the ordered α2 phase in a near-α titanium alloy10.1016/j.scriptamat.2016.02.015 ↗
22. Characterizing nanoscale precipitation in a titanium alloy by laser-assisted atom probe tomography10.1016/j.matchar.2018.04.016 ↗
23. A transmission electron microscopy and three-dimensional atom probe study of the oxygen-induced fine microstructural features in as-sintered Ti–6Al–4V and their impacts on ductility10.1016/j.actamat.2014.01.015 ↗
24. In-service materials support for safety critical applications – A case study of a high strength Ti-alloy using advanced experimental and modelling techniques
25. The effect of oxidation on the subsurface microstructure of a Ti-6Al-4V alloy10.1016/j.scriptamat.2018.01.015 ↗
26. A study of the interaction of oxygen with the α2 phase in the model alloy Ti–7wt%Al10.1016/j.scriptamat.2020.03.048 ↗
27. In situ site-specific specimen preparation for atom probe tomography
28. Field-ion specimen preparation using focused ion-beam milling
29. Lukas · 2007
30. Modeling the oxidation kinetics of titanium alloys: Review, method and application to Ti-64 and Ti-6242s alloys
31. The O-Ti (Oxygen-Titanium) System
32. Efficient, durable protection of the Ti6242S titanium alloy against high-temperature oxidation through MOCVD processed amorphous alumina coatings10.1007/s10853-019-04277-y ↗
33. The ternary system titanium-aluminum-nitrogen10.1016/0022-4596(84)90100-2 ↗
34. The N-Ti (Nitrogen-Titanium) system10.1007/BF02869274 ↗
35. The Al-O-Ti (Aluminum-oxygen-titanium) system10.1361/105497102770331271 ↗
36. Neutron diffraction study of oxygen dissolution in α2-Ti3Al10.1016/j.intermet.2005.04.011 ↗