Aluminizing for enhanced oxidation resistance of ductile refractory high-entropy alloys

Sheikh, Saad Ahmed; Gan, Lu; Tsao, Te Kang; Murakami, Hideyuki; Shafeie, Samrand; Guo, Sheng

doi:10.1016/j.intermet.2018.10.004

Cited by 55 publications

(16 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The alternative approach is to use protective coatings. Particularly, a recent work [32] reported an effective way to improve the oxidation resistance of the Hf 0.5 Nb 0.5 Ta 0.5 Ti 1.5 Zr RHEA with initially poor oxidation resistance through aluminizing. Nevertheless, the information obtained in the current study can help in the design of RHEAs with a balanced combination of properties including (but not limited to) low density, high strength, sufficient ductility, and good oxidation resistance.…”

Section: Discussionmentioning

confidence: 99%

“…However, refractory elements and their alloys are generally vulnerable to oxidation. A number of studies focused on oxidation behavior of different RHEAs [23,24,25,26,27,28,29,30,31,32,33] have demonstrated that some of them possess much better oxidation resistance than conventional refractory alloys; however, the oxidation behavior strongly depended on the alloy composition and testing conditions. Note that the vast majority of the performed research was conducted at temperatures of T ≥ 1000 °C [23,24,25,26,27,28,33].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Oxidation Behavior of Refractory AlNbTiVZr0.25 High-Entropy Alloy

et al. 2018

View full text Add to dashboard Cite

Oxidation behavior of a refractory AlNbTiVZr0.25 high-entropy alloy at 600–900 °C was investigated. At 600–700 °C, two-stage oxidation kinetics was found: Nearly parabolic oxidation (n = 0.46–0.48) at the first stage, transitioned to breakaway oxidation (n = 0.75–0.72) at the second stage. At 800 °C, the oxidation kinetics was nearly linear (n = 0.92) throughout the entire duration of testing. At 900 °C, the specimen disintegrated after 50 h of testing. The specific mass gains were estimated to be 7.2, 38.1, and 107.5, and 225.5 mg/cm2 at 600, 700, and 800 °C for 100 h, and 900 °C for 50 h, respectively. Phase compositions and morphology of the oxide scales were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was shown that the surface layer at 600 °C consisted of the V2O5, VO2, TiO2, Nb2O5, and TiNb2O7 oxides. Meanwhile, the scale at 900 °C comprised of complex TiNb2O7, AlNbO4, and Nb2Zr6O17 oxides. The oxidation mechanisms operating at different temperatures were discussed and a comparison of oxidation characteristics with the other alloys was conducted.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Oxidation Behavior of Refractory AlNbTiVZr0.25 High-Entropy Alloy

et al. 2018

View full text Add to dashboard Cite

show abstract

“…An equimolar NbZrTiCrAl refractory high-entropy alloys was found to follow the parabolic rate law between 800 and 1000 • C, where a dense oxide layer formed with CrNbO 4 , ZrO 2 , TiO 2 , and Al 2 O 3 and followed linear oxidation kinetics; above 1200 • C, it had less oxidation resistance [68]. For the first time, aluminizing was done on the ductile RHEA Al 0.5 Cr 0.5 Nb 0.5 Ta 0.5 Ti 0.5 to increase oxidation resistance; it was reported that when using the one-step process, cracks were seen on the protective layer [69]. To strengthen the layer, a two-step process was done to give a dense layer [70].…”

Section: Oxidation Behaviormentioning

confidence: 99%

A Review of the Latest Developments in the Field of Refractory High-Entropy Alloys

et al. 2021

View full text Add to dashboard Cite

This review paper provides insight into current developments in refractory high-entropy alloys (RHEAs) based on previous and currently available literature. High-temperature strength, high-temperature oxidation resistance, and corrosion resistance properties make RHEAs unique and stand out from other materials. RHEAs mainly contain refractory elements like W, Ta, Mo, Zr, Hf, V, and Nb (each in the 5–35 at% range), and some low melting elements like Al and Cr at less than 5 at%, which were already developed and in use for the past two decades. These alloys show promise in replacing Ni-based superalloys. In this paper, various manufacturing processes like casting, powder metallurgy, metal forming, thin-film, and coating, as well as the effect of different alloying elements on the microstructure, phase formation, mechanical properties and strengthening mechanism, oxidation resistance, and corrosion resistance, of RHEAs are reviewed.

show abstract

“…There are a number of studies of the behavior of refractory HEAs during high-temperature oxidation [ 49 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 ]. The most interesting results are given below; the role of aluminum in oxidation resistance should be noted.…”

Section: High-entropy Alloys From Refractory Metalsmentioning

confidence: 99%

High-Temperature Oxidation of High-Entropic Alloys: A Review

et al. 2021

View full text Add to dashboard Cite

Over the past few years, interest in high-entropic alloys (HEAs) has been growing. A large body of research has been undertaken to study aspects such as the microstructure features of HEAs of various compositions, the effect of the content of certain elements on the mechanical properties of HEAs, and, of course, special properties such as heat resistance, corrosion resistance, resistance to irradiation with high-energy particles, magnetic properties, etc. However, few works have presented results accumulated over several years, which can complicate the choice of directions for further research. This review article presents the results of studies of the mechanisms of high-temperature oxidation of HEAs of systems: Al-Co-Cr-Fe-Ni, Mn-Co-Cr-Fe-Ni, refractory HEAs. An analysis made it possible to systematize the features of high-temperature oxidation of HEAs and propose new directions for the development of heat-resistant HEAs. The presented information may be useful for assessing the possibility of the practical application of HEAs in the aerospace industry, in nuclear and chemical engineering, and in new areas of energy.

show abstract

Aluminizing for enhanced oxidation resistance of ductile refractory high-entropy alloys

Cited by 55 publications

References 51 publications

Oxidation Behavior of Refractory AlNbTiVZr0.25 High-Entropy Alloy

Oxidation Behavior of Refractory AlNbTiVZr0.25 High-Entropy Alloy

A Review of the Latest Developments in the Field of Refractory High-Entropy Alloys

High-Temperature Oxidation of High-Entropic Alloys: A Review

Contact Info

Product

Resources

About