Formation and Oxidation Behavior of a Diffusion-Barrier-Coating System on a Ni–Mo base Alloy at 1,373 K in Air

NiCrAlY coatings with and without CrN or CrON interlayer as diffusion barrier were deposited on superalloy DSM11 by arc ion plating (AIP). The oxidation performance of the coating systems was evaluated by isothermal oxidation tests at 1100 °C for 100 h. The element interdiffusion and oxidation behavior of the coating systems were described. It was found that the NiCrAlY coatings provided protective effect for the DSM11 substrate. However, serious interdiffusion between the coatings and substrate resulted in rapid degradation of the coatings. The addition of CrN or CrON interlayer between the coatings and substrate markedly decreased the interdiffusion. CrON interlayer performed better than CrN interlayer, which was attributed to the excellent diffusion barrier ability of Al2O3 layer formed in the interlayer at high temperature. Also, the NiCrAlY/CrON coating system exhibited more effective protection for DSM11 than the NiCrAlY/CrN coating system.

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High temperature oxidation behavior of hafnium modified NiAl bond coat in EB-PVD thermal barrier coating system

Thin Solid Films ◽

10.1016/j.tsf.2007.07.031 ◽

2008 ◽

Vol 516 (16) ◽

pp. 5732-5735 ◽

Cited By ~ 94

Author(s):

Hongbo Guo ◽

Lidong Sun ◽

Hefei Li ◽

Shengkai Gong

Keyword(s):

High Temperature ◽

Thermal Barrier Coating ◽

Bond Coat ◽

High Temperature Oxidation ◽

Oxidation Behavior ◽

Thermal Barrier ◽

Coating System ◽

Temperature Oxidation ◽

Barrier Coating ◽

High Temperature Oxidation Behavior

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Formation of Pt-Modified γ’-Ni3Al and Re-Based σ-Alloy Coating System and Cyclic Oxidation Behavior of Coated Superalloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.595-598.135 ◽

2008 ◽

Vol 595-598 ◽

pp. 135-141 ◽

Cited By ~ 2

Author(s):

Toshio Narita ◽

Stewart Ford ◽

Takayuki Yoshioka ◽

Takumi Nishimoto ◽

Takeshi Izumi ◽

...

Keyword(s):

Single Crystal ◽

Cyclic Oxidation ◽

Oxidation Behavior ◽

Parabolic Rate Constant ◽

Alloy Coating ◽

Coating System ◽

Barrier Coating ◽

Coated Alloy ◽

Α Al2o3 ◽

Slow Growing

A duplex layer, outer Pt-modified γ’-Ni3Al + γ-Ni and inner multi-barrier σ- Re(Cr,Ni,W), coating system was formed on a Ni-based single crystal 4th generation superalloy. Oxidation behavior of the coated alloy was investigated under thermo-cycling conditions, and analyzed by EPMA and XRD. During cyclic oxidation 1hr at 1100°C and 20 min at room temperature, a slow growing α-Al2O3 formed for up to 400 cycles and its spallation was rare. The parabolic rate constant of mass change was 6.3x10-16 kg2m-4s-1. The Pt-modified γ’-Ni3Al + γ-Ni contained 19Al, 12Pt, 4Cr, and 3Co in at%, and their concentration profiles were almost flat across the outer layer. The multi-barrier, σ-Re(Cr,Ni,W) contained 40Re, 23Cr, 17Ni, 7Al, 4W, 3.5Mo, and 3Co in at%. Furthermore, the γ’-Ni3Al containing Pt was newly formed between the multibarrier and bulk alloy substrate. It was concluded that the σ-Re(Cr,Ni,W) is compatible with the Ptmodified γ’-Ni3Al in the multi-diffusion barrier coating on Ni-based single crystal, 4th generation superalloy at high temperatures.

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The Role of Bond Coat in Advanced Thermal Barrier Coating

Materials Science Forum ◽

10.4028/www.scientific.net/msf.502.99 ◽

2005 ◽

Vol 502 ◽

pp. 99-104 ◽

Cited By ~ 16

Author(s):

Toshio Narita ◽

Shigenari Hayashi ◽

Feng Qun Lang ◽

Kemas Zaini Thosin

Keyword(s):

Diffusion Barrier ◽

Bond Coat ◽

Sigma Phase ◽

Oxidation Behavior ◽

Layer Structure ◽

Thermal Barrier ◽

Outward Diffusion ◽

Hastelloy X ◽

Barrier Coating

A novel diffusion barrier bond coat with a duplex layer structure, a sigma phase Re-Cr-Ni barrier and Ni aluminides as an aluminum reservoir was formed on a Ni based superalloy (TMS 82+) and Hastelloy X. The oxidation behavior of both alloys with and without the sigma- Re-Cr-Ni -phase as a diffusion barrier was investigated at temperatures of 1373K (Hastelloy X) and 1423K (TMS-82+) for up to 360ks. It was found that the Re-Cr-Ni acts as a diffusion barrier for both inward diffusion of Al and outward diffusion of alloying elements in the alloy substrate.

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