Improving oxidation resistance and thermal insulation of thermal barrier coatings by intense pulsed electron beam irradiation

The bond coat of a NiCrAlY thermal barrier coating plays an important role in solving the thermal expansion mismatch between a metal matrix and a ceramic layer and in improving the oxidation resistance of the whole thermal barrier coating. However, the NiCrAlY bond coat prepared by low-pressure plasma spraying is not conducive to its oxidation resistance because its lamellar structure is loose, porous and the surface is rough. To improve the oxidation resistance of the bond coat, the NiCrAlY bond coat prepared by plasma spraying was modified by high-current pulsed electron beam with different energy densities. Under the electron beam irradiation, the surface of the coating became smooth, and there was a 3–5 μm thick remelting layer on the surface. Under the irradiation, the thickness of the thermal growth oxide layer decreased, and the oxidation resistance was significantly improved, the oxidation product being mainly Al2O3.

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Isothermal oxidation behaviour of thermal barrier coatings with CoCrAlY bond coat irradiated by high-current pulsed electron beam

Applied Surface Science ◽

10.1016/j.apsusc.2014.08.049 ◽

2014 ◽

Vol 317 ◽

pp. 360-369 ◽

Cited By ~ 34

Author(s):

Jie Cai ◽

Qingfeng Guan ◽

Xiuli Hou ◽

Zhiping Wang ◽

Jingxin Su ◽

...

Keyword(s):

Electron Beam ◽

Thermal Barrier Coatings ◽

Bond Coat ◽

Isothermal Oxidation ◽

Oxidation Behaviour ◽

Thermal Barrier ◽

High Current ◽

Barrier Coatings ◽

Pulsed Electron Beam

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Adhesion Strength of Thermal Barrier Coatings with Thermal-Sprayed Bondcoat Treated by Compound Method of High-Current Pulsed Electron Beam and Grit Blasting

Journal of Thermal Spray Technology ◽

10.1007/s11666-015-0241-3 ◽

2015 ◽

Vol 24 (5) ◽

pp. 798-806 ◽

Cited By ~ 12

Author(s):

Jie Cai ◽

Qingfeng Guan ◽

Peng Lv ◽

Xiuli Hou ◽

Zhiping Wang ◽

...

Keyword(s):

Electron Beam ◽

Thermal Barrier Coatings ◽

Adhesion Strength ◽

Thermal Barrier ◽

High Current ◽

Barrier Coatings ◽

Grit Blasting ◽

Pulsed Electron Beam ◽

Compound Method

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Numerical Simulation for Surface Modification of Thermal Barrier Coatings by High-Current Pulse Electron Beam

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1807 ◽

2010 ◽

Vol 654-656 ◽

pp. 1807-1810

Author(s):

Ying Qin ◽

Wei Qu ◽

Xian Xiu Mei ◽

Sheng Zhi Hao ◽

Ji Jun Zhao ◽

...

Keyword(s):

Electron Beam ◽

Thermal Barrier Coatings ◽

Physical Vapor Deposition ◽

Turbine Blades ◽

Ceramic Coatings ◽

Pulse Electron Beam ◽

Thermal Barrier ◽

High Current ◽

Barrier Coatings ◽

Pulsed Electron Beam

High current pulsed electron beam is an effective technique for surface sealing of ceramic thermal barrier coatings prepared by electron beam physical vapor deposition. Due to the rapid remelting and solidification, the outer layers of ceramic coatings become smooth and dense, and the protective performance for turbine blades is effectively improved. Because of the complex multi-layered structures in the coatings, a high-current pulsed electron beam treatment requires specific parameter inputs which are related to the temperature field induced by electron energy deposition in the coatings. In this paper, a two-dimensional temperature simulation was performed to demonstrate the melting depth and temperature evolution in ceramic coatings treated by high-current pulsed electron beam. Different energy densities and pulses were studied and discussed for obtaining optimized parameters.

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