Effect of Pt Content on TGO Growth in EB-PVD TBC Systems with Niptal Bondcoats

The oxidation behavior of Pt modified aluminide coating on the CMSX-4 Ni-base alloy plays major role to the EB-PVD TBC failure. The thermally growth oxide (TGO) is one of the most important factors to affect TBC lifetime. Two different Pt-content NiPtAl coatings in EB-PVD TBC systems were studied at 1100°C in air. The results indicated that cross-sections of oxide layer on the NiPtAl coatings within TBC in air were similar for the both bondcoats. The cracks could be found on the TBC/TGO/BC interfaces for the two bondcoats. The TGO morphologies of the low and high-Pt bondcoats on the side without TBC showed great different due to small PtAl particles size within high-Pt bondcoats. The irregular alumina on the both bondcoats was also showed on the sides with TBC compared to ones without TBC due to absence of the TBC. The TGO growth on the high-Pt bondcoats was faster than the low-Pt coatings during initial oxidation time. With the time increasing, the high-Pt content could suppress the TGO growth rate. Thinner TGO thickness could be obeserved on the both NiPtAl coatings due to the stress in TGO accumulation and oxide spallation.

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Parameters affecting TGO growth rate and the lifetime of TBC systems with MCrAlY-bondcoats

Materials and Corrosion ◽

10.1002/maco.200804134 ◽

2008 ◽

Vol 59 (6) ◽

pp. 501-507 ◽

Cited By ~ 32

Author(s):

J. Toscano ◽

D. Naumenko ◽

A. Gil ◽

L. Singheiser ◽

W. J. Quadakkers

Keyword(s):

Growth Rate ◽

Tbc Systems ◽

Tgo Growth

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Oxidation behavior of non-stoichiometric (Zr,Hf,Ti)Cx carbide solid solution powders in air

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0469-y ◽

2021 ◽

Author(s):

Huilin Lun ◽

Yi Zeng ◽

Xiang Xiong ◽

Ziming Ye ◽

Zhongwei Zhang ◽

...

Keyword(s):

Solid Solution ◽

Oxidation Resistance ◽

Oxidation Behavior ◽

Group Iv ◽

Hypersonic Vehicles ◽

Metal Carbides ◽

Initial Oxidation ◽

Plasma Sintering ◽

Spark Plasma ◽

Kinetics Of

AbstractMulti-component solid solutions with non-stoichiometric compositions are characteristics of ultra-high temperature carbides as promising materials for hypersonic vehicles. However, for group IV transition-metal carbides, the oxidation behavior of multi-component non-stoichiometric (Zr,Hf,Ti)Cx carbide solid solution has not been clarified yet. The present work fabricated four kinds of (Zr,Hf,Ti)Cx carbide solid solution powders by free-pressureless spark plasma sintering to investigate the oxidation behavior of (Zr,Hf,Ti)Cx in air. The effects of metallic atom composition on oxidation resistance were examined. The results indicate that the oxidation kinetics of (Zr,Hf,Ti)Cx are composition dependent. A high Hf content in (Zr,Hf,Ti)Cx was beneficial to form an amorphous Zr-Hf-Ti-C-O oxycarbide layer as an oxygen barrier to enhance the initial oxidation resistance. Meanwhile, an equiatomic ratio of metallic atoms reduced the growth rate of (Zr,Hf,Ti)O2 oxide, increasing its phase stability at high temperatures, which improved the oxidation activation energy of (Zr, Hf, Ti)Cx.

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Isothermal Oxidation Behavior of Ru Modified Aluminide Coating on a Fourth Generation Single Crystal Superalloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.512.111 ◽

2006 ◽

Vol 512 ◽

pp. 111-116 ◽

Cited By ~ 1

Author(s):

Yuki Matsuoka ◽

Kazuyoshi Chikugo ◽

Takakazu Suzuki ◽

Yasuo Matsunaga ◽

Shigeji Taniguchi

Keyword(s):

Phase Transformation ◽

Oxidation Behavior ◽

Coating Layer ◽

Aluminide Coating ◽

Isothermal Oxidation ◽

Fourth Generation ◽

Short Term ◽

Cross Sectional ◽

Local Oxidation ◽

Sectional Analysis

Ru coating prior to aluminizing is one of the effective methods to reduce the harmful intermediate layer that forms under the coating (SRZ) on a 4th generation Ni-base SC superalloy. This study examined the short-term isothermal oxidation behavior of this Ru-modified coating at 1373 K in air. Surface observation by SEM showed that the scale becomes flat and uniform in comparison to simple aluminide coating. XRD and cross-sectional analysis results also showed that phase transformation from β-NiAl to γ’-Ni3Al seldom occurs in the Ru-modified coating layer leading to the prevention of local oxidation.

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Oxidation Behavior of Ferritic Steel T22 Exposed to Supercritical Water

High Temperature Materials and Processes ◽

10.1515/htmp-2018-0100 ◽

2019 ◽

Vol 38 (2019) ◽

pp. 476-484 ◽

Cited By ~ 3

Author(s):

Zhongliang Zhu ◽

Hasan Izhar Khan ◽

Qi Cao ◽

Naiqiang Zhang

Keyword(s):

Iron Oxide ◽

Supercritical Water ◽

Layered Structure ◽

Outer Layer ◽

Ferritic Steel ◽

Oxidation Behavior ◽

Spinel Oxide ◽

Initial Oxidation ◽

Exposure Temperature ◽

Oxidation Stage

AbstractThe oxidation tests of Ferritic Steel T22 exposed to supercritical water (SCW) at 540–620°C and 25 MPa was performed for up to 1000 h. The oxidation rate increased with increasing exposure temperature and time. Oxide films formed on T22 have a double-layered structure with an outer layer consisting of iron oxide and an inner layer consisting of spinel oxide. Numerous pores on the surface can be observed at the initial oxidation stage while they seemed to heal with increasing exposure time at 620°C. Cracks occurred along grain boundaries in the oxide scale when T22 exposed for 200 h at 620°C. The influence of time and temperature on the oxidation of Ferritic Steel T22 was discussed.

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In Situ Study on the Initial Oxidation Behavior of Zirconium Alloys with Near-Ambient Pressure XPS

Acta Physico-Chimica Sinica ◽

10.3866/pku.whxb202003026 ◽

2020 ◽

Vol 0 (0) ◽

pp. 2003026-0

Author(s):

Jiuxiang Dai ◽

Zhongmiao Gong ◽

Shitong Xu ◽

Yi Cui ◽

Meiyi Yao

Keyword(s):

Oxidation Behavior ◽

Ambient Pressure ◽

Zirconium Alloys ◽

Initial Oxidation ◽

Ambient Pressure Xps ◽

Near Ambient Pressure Xps

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Effect of Phase Fraction Ratio Between Al3Mg2 and Mg2Si on the Oxidation Behavior of Al–Mg–Si Alloys

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2021.3018 ◽

2021 ◽

Vol 16 (7) ◽

pp. 1047-1051

Author(s):

Seong-Ho Ha ◽

Abdul Wahid Shah ◽

Bong-Hwan Kim ◽

Young-Ok Yoon ◽

Hyun-Kyu Lim ◽

...

Keyword(s):

Oxidation Resistance ◽

High Temperatures ◽

Cross Sections ◽

Oxidation Behavior ◽

Eutectic Phase ◽

Mg Alloy ◽

Phase Fraction ◽

The Matrix ◽

Si Content

The effect of the phase fraction ratio between Al3Mg2 and Mg2Si on the oxidation resistance of Al–Mg–Si alloys at high temperatures was investigated. With addition of 1 mass%Si in Al-6 mass%Mg alloy, the as-cast microstructures showed formation of Mg2Si phase by eutectic reactions. With increasing Si content more than 3 mass%, the Mg2Si and Si are formed as eutectic phases with no β-Al3Mg2 phase. In addition, with an increase in the Si content from 3 mass%, significantly refined as-cast microstructures and distribution of extended eutectic phase areas were observed. The oxidized cross-sections of Al-6 mass%Mg and Al-6 mass%Mg-1 mass%Si alloys showed coarse and dark areas, which are considered as oxide clusters, nonuniformly grown into the matrix. However, Al-6 mass%Mg-3 mass%Si and Al-6 mass%Mg-5 mass%Si alloys had no significantly grown oxide clusters on the surfaces. Based on the results, it was concluded that the reduction of the ratio between β-Al3Mg2 and Mg2Si phases can reduce the rapid oxidation of Mg.

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